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<h1>Server Tuning</h1><h2 id="top">Table of
Contents</h2><section class="toc"><section
class="toc-row"><header>General</header><p>
<a href="#ramDiskPath">RAM Disk Path</a> | <a
href="#shmDefaultDir">Default SHM Directory</a> | <a
href="#bindIPv6Only">Bind IPv6 Only</a> | <a
href="#reverseDnsLookup">Reverse DNS Lookup</a> | <a
href="#verifyGoogleBot">Verify Google Bot</a> | <a
href="#forceSecureCookie">Secure Cookie Control</a> |
<a href="#proxyProtocol">PROXY
protocol</a></p></section>
<section
class="toc-row"><header>Connection</header><p>
<a href="#maxConnections">Max Connections</a> | <a
href="#maxSSLConnections">Max SSL Connections</a> |
<a href="#connTimeout">Connection Timeout (secs)</a>
| <a href="#maxKeepAliveReq">Max Keep-Alive
Requests</a> | <a href="#keepAliveTimeout">Keep-Alive
Timeout (secs)</a> | <a href="#sndBufSize">Send
Buffer Size (bytes)</a> | <a
href="#rcvBufSize">Receive Buffer Size
(bytes)</a></p></section>
<section
class="toc-row"><header>Request/Response</header><p>
<a href="#maxReqURLLen">Max Request URL Length
(bytes)</a> | <a href="#maxReqHeaderSize">Max Request
Header Size (bytes)</a> | <a
href="#maxReqBodySize">Max Request Body Size (bytes)</a>
| <a href="#maxDynRespHeaderSize">Max Dynamic Response
Header Size (bytes)</a> | <a
href="#maxDynRespSize">Max Dynamic Response Body Size
(bytes)</a></p></section>
<section class="toc-row"><header>Static File Delivery
Optimization</header><p>
<a href="#maxCachedFileSize">Max Cached Small File Size
(bytes)</a> | <a href="#totalInMemCacheSize">Total
Small File Cache Size (bytes)</a> | <a
href="#maxMMapFileSize">Max MMAP File Size (bytes)</a> |
<a href="#totalMMapCacheSize">Total MMAP Cache Size
(bytes)</a> | <a href="#useSendfile">Use
sendfile()</a> | <a href="#useAIO">Use AIO</a>
| <a href="#AIOBlockSize">AIO Block Size</a> | <a
href="#fileETag">File ETag</a></p></section>
<section class="toc-row"><header>GZIP/Brotli
Compression</header><p>
<a href="#enableGzipCompress">Enable Compression</a>
| <a href="#compressibleTypes">Compressible Types</a>
| <a href="#enableDynGzipCompress">Enable GZIP Dynamic
Compression</a> | <a href="#gzipCompressLevel">GZIP
Compression Level (Dynamic Content)</a> | <a
href="#enableBrCompress">Brotli Compression Level (Dynamic
Content)</a> | <a href="#gzipAutoUpdateStatic">Auto
Update Static File</a> | <a
href="#gzipStaticCompressLevel">GZIP Compression Level (Static
File)</a> | <a href="#brStaticCompressLevel">Brotli
Compression Level (Static File)</a> | <a
href="#gzipCacheDir">Static Cache Directory</a> | <a
href="#gzipMaxFileSize">Max Static File Size (bytes)</a>
| <a href="#gzipMinFileSize">Min Static File Size
(bytes)</a></p></section>
<section class="toc-row"><header>SSL Global
Settings</header><p>
<a href="#sslDefaultCiphers">Default Cipher Suite</a>
| <a href="#sslStrongDhKey">SSL Strong DH Key</a> |
<a href="#sslEnableMultiCerts">Enable Multiple SSL
Certificates</a> | <a href="#sslCertCompress">Enable
Certificate Compression</a> | <a
href="#sslHsOffload">Enable Handshake Offload</a> |
<a href="#sslSessionCache">Enable Session Cache</a> |
<a href="#sslSessionCacheSize">Session Cache Size
(bytes)</a> | <a
href="#sslSessionCacheTimeout">Session Cache Timeout
(secs)</a> | <a href="#sslSessionTickets">Enable
Session Tickets</a> | <a
href="#sslSessionTicketLifetime">SSL Session Ticket Lifetime
(secs)</a> | <a href="#sslSessionTicketKeyFile">SSL
Session Ticket Key File</a> | <a
href="#sslOcspProxy">OCSP Proxy</a> | <a
href="#sslStrictSni">Strict SNI
Certificate</a></p></section>
<section
class="toc-row"><header>HTTP3/QUIC</header><p>
<a href="#quicEnable">Enable HTTP3/QUIC</a> | <a
href="#quicShmDir">QUIC SHM Directory</a> | <a
href="#quicVersions">HTTP3/QUIC Versions</a> | <a
href="#quicCongestionCtrl">Congestion Control</a> |
<a href="#quicCfcw">Connection Flow Control
Window</a> | <a href="#quicMaxCfcw">Max Connection
Flow Control Window</a> | <a href="#quicSfcw">Stream
Flow Control Window</a> | <a href="#quicMaxSfcw">Max
Stream Flow Control Window</a> | <a
href="#quicMaxStreams">Max Concurrent Streams Per
Connection</a> | <a
href="#quicHandshakeTimeout">Handshake Timeout</a> |
<a href="#quicIdleTimeout">Idle Timeout</a> | <a
href="#quicEnableDPLPMTUD">Enable DPLPMTUD</a> | <a
href="#quicBasePLPMTU">PLPMTU Base Value</a> | <a
href="#quicMaxPLPMTU">PLPMTU Max
Value</a></p></section>
</section>
<section><div class="helpitem"><article
class="ls-helpitem"><div><header
id="ramDiskPath"><h3>RAM Disk Path<span
class="ls-permlink"><a
href="#ramDiskPath"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Setting
the RAM Disk Path allows you to designate the location of a RAM disk. A RAM
disk is a world-writable directory stored in memory. A server with excess
RAM can reduce disk I/O by serving content from this RAM disk. Accessing
content from RAM is much faster than reading data from the disk. LSWS will
use this RAM disk to optimize performance when there is enough memory
available.<br/><br/> (The RAM disk must be designated in your
OS setup before it can be used by the web server. Many Linux distributions
assign /dev/shm as a RAM disk by default, but these settings depend on your
OS.)</p> <h4>Syntax</h4><p>path</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="shmDefaultDir"><h3>Default SHM Directory<span
class="ls-permlink"><a
href="#shmDefaultDir"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Changes
shared memory's default directory to the specified path. If the
directory does not exist, it will be created. All SHM data will be stored
in this directory unless otherwise specified.</p>
<h4>Syntax</h4><p>path</p> </article>
</div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="bindIPv6Only"><h3>Bind IPv6 Only<span
class="ls-permlink"><a
href="#bindIPv6Only"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Only
bind IPv6 for IPv6 wildcard IP addresses. When set to "Yes", IPv4
IP addresses will not be bound and will need their own
listeners.<br/><br/> Default value: Yes</p>
<h4>Syntax</h4><p>Select from radio box</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="reverseDnsLookup"><h3>Reverse DNS Lookup<span
class="ls-permlink"><a
href="#reverseDnsLookup"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Perform
an IP -> Domain Name lookup for each client. This can be used in access
logging.<br/><br/> Default value: No</p>
<h4>Syntax</h4><p>Select from radio box</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="verifyGoogleBot"><h3>Verify Google Bot<span
class="ls-permlink"><a
href="#verifyGoogleBot"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Perform
a PTR lookup to ensure that the reverse DNS of an IP matches Google's
crawler information and bypass reCAPTCHA verification if so. Bad Google
bot IPs are logged.<br/><br/> Default value: No</p>
<h4>Syntax</h4><p>Select from radio box</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="forceSecureCookie"><h3>Secure Cookie Control<span
class="ls-permlink"><a
href="#forceSecureCookie"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Control
whether to send cookies with the flag "secure", attribute
"SameSite=Strict", and attribute
"SameSite=Lax".<br/><br/> If both
"SameSite=Strict" and "SameSite=Lax" are selected,
"SameSite=Strict" will be used.<br/><br/> Default
value: "secure"</p>
<h4>Syntax</h4><p>Select from checkbox</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="proxyProtocol"><h3>PROXY protocol<span
class="ls-permlink"><a
href="#proxyProtocol"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>List
of IPs/subnets for front-end proxies that communicate with this server
using PROXY protocol. Once set, the server will use PROXY protocol for
incoming connections from listed IPs/subnets or fall back to a regular
connection if PROXY protocol is unavailable.<br/><br/> Applies
to HTTP, HTTPS, HTTP2, and websocket connections.</p>
<h4>Syntax</h4><p>Comma delimited list of IP addresses or
sub-networks.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="maxConnections"><h3>Max Connections<span
class="ls-permlink"><a
href="#maxConnections"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the maximum number of concurrent connections that the server can accept.
This includes both plain TCP connections and SSL connections. This setting
should not be set to exceed the hard limit set by the server software
edition or license: <span class="val">500</span> for
VPS license, <span class="val">800</span> for Ultra
VPS license. Once the maximum concurrent connections limit is reached, the
server will close Keep-Alive connections when they complete active
requests.</p> <h4>Syntax</h4><p>Integer
number</p> <h4>Tips</h4><p><span
title="Information"
class="ls-icon-info"></span> When the server is started
by "root" user, the server will try to adjust the per-process
file descriptor limits automatically, however, if this fails, you may need
to increase this limit manually.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="maxSSLConnections"><h3>Max SSL Connections<span
class="ls-permlink"><a
href="#maxSSLConnections"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the maximum number of concurrent SSL connections the server will accept.
Since total concurrent SSL and non-SSL connections cannot exceed the limit
specified by <span class="tagl"><a
href="#maxConnections">Max Connections</a></span>,
the actual number of concurrent SSL connections allowed must be lower than
this limit.</p> <h4>Syntax</h4><p>Integer
number</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="connTimeout"><h3>Connection Timeout (secs)<span
class="ls-permlink"><a
href="#connTimeout"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the maximum connection idle time allowed during processing one request. The
connection will be closed if it has been idle, i.e. no I/O activity, for
this period of time.</p> <h4>Syntax</h4><p>Integer
number</p> <h4>Tips</h4><p><span
title="Security"
class="ls-icon-security"></span> Set this as low as you
can to help recover dead connections during a potential DoS
attack.</p> <h4>See Also</h4><p
class="ls-text-small"><span class="tagl"><a
href="#keepAliveTimeout">Keep-Alive Timeout
(secs)</a></span></p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="maxKeepAliveReq"><h3>Max Keep-Alive Requests<span
class="ls-permlink"><a
href="#maxKeepAliveReq"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the maximum number of requests that can be served through a keep-alive
(persistent) session. The connection will be closed once this limit is
reached. You can set this limit for each virtual host as well.</p>
<h4>Syntax</h4><p>Integer number</p>
<h4>Tips</h4><p><span title="Performance"
class="ls-icon-performance"></span> Set this to a
reasonably high value. A value of "1" or "0" will
disable keep-alive.</p> <h4>See Also</h4><p
class="ls-text-small">Virtual Host <span
class="tagl"><a
href="VirtualHosts_Help.html#vhMaxKeepAliveReq">Max Keep-Alive
Requests</a></span></p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="keepAliveTimeout"><h3>Keep-Alive Timeout
(secs)<span class="ls-permlink"><a
href="#keepAliveTimeout"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the maximum idle time between requests from a keep-alive connection. If no
new request is received during this period of time, the connection will be
closed. This setting only applies to HTTP/1.1 connections. HTTP/2
connections have long keep-alive timeouts by design and are not affected by
this setting.</p> <h4>Syntax</h4><p>Integer
number</p> <h4>Tips</h4><p><span
title="Security"
class="ls-icon-security"></span><span
title="Performance"
class="ls-icon-performance"></span> We recommend that
you set this value just long enough to wait for subsequent requests from a
client when there are more assets referenced by a single page that need to
be loaded. Do not set this too long hoping that the next page will be
served over the keep-alive connection. Keeping many idle keep-alive
connections is a waste of server resources and could be taken advantage of
by (D)DoS attacks. <span class="val">2-5</span>
seconds is a reasonable range for most applications. LiteSpeed is highly
efficient in a non-keep-alive environment.</p> </article>
</div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sndBufSize"><h3>Send Buffer Size (bytes)<span
class="ls-permlink"><a
href="#sndBufSize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>The
sending buffer size of each TCP socket. <span
class="val">512K</span> is the maximum allowed buffer
size.</p> <h4>Syntax</h4><p>Integer
number</p> <h4>Tips</h4><p><span
title="Performance"
class="ls-icon-performance"></span> It is recommended to
leave this value as "Not Set" or set to 0 to use the operating
system's default buffer size.<br/> <span
title="Performance"
class="ls-icon-performance"></span> If your web site
serves large static files, increase the send buffer size to improve
performance.<br/> <span title="Performance"
class="ls-icon-performance"></span> Setting this to a
lower value will reduce throughput and memory usage per socket allowing the
server to have more concurrent sockets when memory is a
bottleneck.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="rcvBufSize"><h3>Receive Buffer Size (bytes)<span
class="ls-permlink"><a
href="#rcvBufSize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>The
receiving buffer size of each TCP socket. <span
class="val">512K</span> is the maximum allowed buffer
size.</p> <h4>Syntax</h4><p>Integer
number</p> <h4>Tips</h4><p><span
title="Performance"
class="ls-icon-performance"></span> It is recommended to
leave this value as "Not Set" or set to 0 to use the operating
system's default buffer size.<br/> <span
title="Performance"
class="ls-icon-performance"></span> A large receive
buffer will increase performance when processing incoming requests with
large payloads, i.e. file uploads.<br/> <span
title="Performance"
class="ls-icon-performance"></span> Setting this to a
lower value will reduce throughput and memory usage per socket allowing the
server to have more concurrent sockets when memory is a
bottleneck.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="maxReqURLLen"><h3>Max Request URL Length
(bytes)<span class="ls-permlink"><a
href="#maxReqURLLen"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the maximum size of a request URL. URL is the full text address used to
access a server resource including the query string. Hard limit is <span
class="val">65530</span> bytes. Values larger than this,
such as <span class="val">64K</span> (6 bytes
larger), will be treated as if <span
class="val">65530</span> was used.<br/><br/>
Default value: <span class="val">8192</span> or
<span class="val">8K</span>.</p>
<h4>Syntax</h4><p>Integer number</p>
<h4>Tips</h4><p><span title="Security"
class="ls-icon-security"></span><span
title="Performance"
class="ls-icon-performance"></span> Set it reasonably
low to reduce memory usage and help identify bogus requests and DoS
attacks.<br/> 2-3K is big enough for most web sites unless the HTTP
GET method is used with large query strings instead of POST.</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="maxReqHeaderSize"><h3>Max Request Header Size
(bytes)<span class="ls-permlink"><a
href="#maxReqHeaderSize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the maximum size of an HTTP request header including request URL. Hard
limit is <span class="val">65530</span> bytes. Values
larger than this, such as <span
class="val">64K</span> (6 bytes larger), will be treated
as if <span class="val">65530</span> was
used.<br/><br/> Default value: <span
class="val">32768</span> or <span
class="val">32K</span></p>
<h4>Syntax</h4><p>Integer number</p>
<h4>Tips</h4><p><span title="Security"
class="ls-icon-security"></span><span
title="Performance"
class="ls-icon-performance"></span> Set it reasonably
low to reduce memory usage and help identify bogus requests and DoS
attacks.<br/> 4-8K is big enough for most web sites under normal
circumstances.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="maxReqBodySize"><h3>Max Request Body Size
(bytes)<span class="ls-permlink"><a
href="#maxReqBodySize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the maximum size of an HTTP request body. For a 32Bit OS, <span
class="val">2GB</span> is the hard limit. For a 64Bit
OS, it is virtually unlimited.</p>
<h4>Syntax</h4><p>Integer number</p>
<h4>Tips</h4><p><span title="Security"
class="ls-icon-security"></span> To help prevent DoS
attacks, try to constrain this limit to only what is really needed. Your
swapping space must have enough free space to accommodate this
limit.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="maxDynRespHeaderSize"><h3>Max Dynamic Response
Header Size (bytes)<span class="ls-permlink"><a
href="#maxDynRespHeaderSize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the maximum header size of a dynamically generated response. Hard limit is
<span class="val">65530</span> bytes. Values larger
than this, such as <span class="val">64K</span> (6
bytes larger), will be treated as if <span
class="val">65530</span> was used.<br/><br/>
Default value: <span class="val">32768</span> or
<span class="val">32K</span></p>
<h4>Syntax</h4><p>Integer number</p>
<h4>Tips</h4><p><span title="Performance"
class="ls-icon-performance"></span> Set it reasonably
low to help recognize bad responses dynamically generated by external
applications.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="maxDynRespSize"><h3>Max Dynamic Response Body Size
(bytes)<span class="ls-permlink"><a
href="#maxDynRespSize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the maximum body size of a dynamically generated response.</p>
<h4>Syntax</h4><p>Integer number</p>
<h4>Tips</h4><p><span title="Performance"
class="ls-icon-performance"></span> Set the limit
reasonably low to help identify bad responses. It is not uncommon to
malformed scripts to contain an infinite loop which leads to infinity-sized
responses.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="maxCachedFileSize"><h3>Max Cached Small File Size
(bytes)<span class="ls-permlink"><a
href="#maxCachedFileSize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the largest static file that will be cached in a pre-allocated memory
buffer. Static files can be served in four different ways: memory buffer
cache, memory-mapped cache, plain read/write, and sendfile(). Files whose
size is smaller than this setting are served from memory buffer cache.
Files whose size is larger than this setting, but smaller than the <span
class="tagl"><a href="#maxMMapFileSize">Max
MMAP File Size (bytes)</a></span> will be served from
memory-mapped cache. Files whose size is larger than the <span
class="tagl"><a href="#maxMMapFileSize">Max
MMAP File Size (bytes)</a></span> will be served via plain
read/write or sendfile(). It is optimal to serve static files smaller than
4K from the memory buffer cache.</p>
<h4>Syntax</h4><p>Integer number</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="totalInMemCacheSize"><h3>Total Small File Cache Size
(bytes)<span class="ls-permlink"><a
href="#totalInMemCacheSize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the total memory that can be allocated to the buffer cache in order to
cache/serve small static files.</p>
<h4>Syntax</h4><p>Integer number</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="maxMMapFileSize"><h3>Max MMAP File Size
(bytes)<span class="ls-permlink"><a
href="#maxMMapFileSize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the largest static file that will be memory mapped (MMAP). Static files
can be served in four different ways: memory buffer cache, memory-mapped
cache, plain read/write, and sendfile(). Files whose size is smaller than
the <span class="tagl"><a
href="#maxCachedFileSize">Max Cached Small File Size
(bytes)</a></span> are served from memory buffer cache. Files
whose size is larger than the <span class="tagl"><a
href="#maxCachedFileSize">Max Cached Small File Size
(bytes)</a></span>, but smaller than the Max MMAP File Size
will be served from memory-mapped cache. Files whose size is larger than
the Max MMAP File Size will be served via plain read/write or sendfile().
Since the server has a 32bit address space (2GB), it is not recommended to
memory map very large files.</p>
<h4>Syntax</h4><p>Integer number</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="totalMMapCacheSize"><h3>Total MMAP Cache Size
(bytes)<span class="ls-permlink"><a
href="#totalMMapCacheSize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the total memory that can be allocated for memory- mapped cache in order to
cache/serve medium sized static files.</p>
<h4>Syntax</h4><p>Integer number</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="useSendfile"><h3>Use sendfile()<span
class="ls-permlink"><a
href="#useSendfile"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
whether to use the sendfile() system call to serve static files. Static
files can be served in four different ways: memory buffer cache,
memory-mapped cache, plain read/write, and sendfile(). Files smaller than
the <span class="tagl"><a
href="#maxCachedFileSize">Max Cached Small File Size
(bytes)</a></span> are served from memory buffer cache. Files
larger than the <span class="tagl"><a
href="#maxCachedFileSize">Max Cached Small File Size
(bytes)</a></span> but smaller than the <span
class="tagl"><a href="#maxMMapFileSize">Max
MMAP File Size (bytes)</a></span> will be served from
memory-mapped cache. Files larger than the <span
class="tagl"><a href="#maxMMapFileSize">Max
MMAP File Size (bytes)</a></span> will be served via plain
read/write or sendfile(). Sendfile() is a "zero copy" system call
that can greatly reduce CPU utilization when serving very large static
files. Sendfile() requires an optimized network card kernel driver and thus
may not be suitable for some small-vendor network adapters.</p>
<h4>Syntax</h4><p>Select from radio box</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="useAIO"><h3>Use AIO<span
class="ls-permlink"><a
href="#useAIO"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
whether to use AIO to serve static files. AIO will help if your server has
a high I/O wait. For 64bit operation system, there is an option to keep
files mapped in process address space to improve AIO performance.</p>
<h4>Syntax</h4><p>Select from drop down list</p>
<h4>See Also</h4><p
class="ls-text-small"><span class="tagl"><a
href="#AIOBlockSize">AIO Block
Size</a></span></p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="AIOBlockSize"><h3>AIO Block Size<span
class="ls-permlink"><a
href="#AIOBlockSize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the sent block size for AIO. This block size multiplied by the total files
being processed should be less than the physical memory of the server,
otherwise, AIO will not help. If your server has enough memory, you can
choose a bigger size.<br/><br/> Default value: <span
class="val">1M</span></p>
<h4>Syntax</h4><p>Select from drop down list</p>
<h4>See Also</h4><p
class="ls-text-small"><span class="tagl"><a
href="#useAIO">Use AIO</a></span></p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="fileETag"><h3>File ETag<span
class="ls-permlink"><a
href="#fileETag"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
whether to use a file's inode, last-modified time, and size attributes
to generate the ETag HTTP response header for static files. All three
attributes are enabled by default. If you plan to serve the same file out
of mirrored servers, you should not include inode; otherwise, the ETag
generated for one file will be different on different servers.</p>
<h4>Syntax</h4><p>Select from checkbox</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="enableGzipCompress"><h3>Enable Compression<span
class="ls-permlink"><a
href="#enableGzipCompress"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Enables
GZIP/Brotli compression for both static and dynamic
responses.<br/><br/> Default value: Yes</p>
<h4>Syntax</h4><p>Select from radio box</p>
<h4>Tips</h4><p><span title="Performance"
class="ls-icon-performance"></span> Enable it to save
network bandwidth. Text-based responses such as html, css, and javascript
files benefit the most and on average can be compressed to half of their
original size.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="compressibleTypes"><h3>Compressible Types<span
class="ls-permlink"><a
href="#compressibleTypes"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
what MIME types are allowed to be compressed. Leave this setting unset or
enter <span class="val">default</span> to use the
server built-in default list which should already cover most
mime-types.<br/><br/> Default value: <span
class="val">text/*,application/x-javascript,application/javascript,application/xml,image/svg+xml,application/rss+xml,
application/json,application/vnd.ms-fontobject,application/x-font,application/x-font-opentype,
application/x-font-truetype,application/x-font-ttf,font/eot,font/opentype,font/otf,font/ttf,image/x-icon,
image/vnd.microsoft.icon,application/xhtml+xml</span></p>
<h4>Syntax</h4><p>MIME type list separated by commas.
Wild card "*" and negate sign "!" are allowed, such as
text/*, !text/js.</p> <h4>Example</h4><div
class="ls-example">If you want to compress text/* but not
text/css, you can have a rule like <span
class="val">text/*, !text/css</span>. "!" will
exclude that MIME
type.</div><h4>Tips</h4><p><span
title="Performance"
class="ls-icon-performance"></span> Only allow types
that will benefit from GZIP/Brotli compression. Binary files such as
gif/png/jpeg images and flash files do not benefit from
compression.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="enableDynGzipCompress"><h3>Enable GZIP Dynamic
Compression<span class="ls-permlink"><a
href="#enableDynGzipCompress"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Controls
GZIP compression for dynamically generated responses.<br/><br/>
For this setting to have an effect, <span
class="tagl"><a
href="#enableGzipCompress">Enable
Compression</a></span> must be set to <span
class="val">Yes</span>.<br/><br/> Default
value: Yes</p> <h4>Syntax</h4><p>Select from radio
box</p> <h4>Tips</h4><p><span
title="Performance"
class="ls-icon-performance"></span> Compressing dynamic
responses increases CPU and memory utilization but saves network
bandwidth.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="gzipCompressLevel"><h3>GZIP Compression Level
(Dynamic Content)<span class="ls-permlink"><a
href="#gzipCompressLevel"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the level of GZIP compression applied to dynamic content. Ranges from
<span class="val">1</span> (lowest) to <span
class="val">9</span> (highest).<br/><br/>
This setting will only take effect when <span
class="tagl"><a
href="#enableGzipCompress">Enable
Compression</a></span> and <span
class="tagl"><a
href="#enableDynGzipCompress">Enable GZIP Dynamic
Compression</a></span> are enabled.<br/><br/>
Default value: 6</p> <h4>Syntax</h4><p>Number
between 1 and 9.</p> <h4>Tips</h4><p><span
title="Performance"
class="ls-icon-performance"></span> Higher compression
level will use more memory and CPU cycles. You can set it to a higher level
if your machine has additional power. There is not much difference between
6 and 9, except that 9 uses many more CPU cycles.</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="enableBrCompress"><h3>Brotli Compression Level
(Dynamic Content)<span class="ls-permlink"><a
href="#enableBrCompress"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Controls
the level of Brotli compression applied to dynamic responses. Ranges from
<span class="val">0</span> (OFF) to <span
class="val">6</span> (highest).<br/><br/>
This setting will only take effect when <span
class="tagl"><a
href="#enableGzipCompress">Enable
Compression</a></span> is enabled.<br/><br/>
Default value: 2</p> <h4>Syntax</h4><p>Number
between 0 and 6.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="gzipAutoUpdateStatic"><h3>Auto Update Static
File<span class="ls-permlink"><a
href="#gzipAutoUpdateStatic"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
whether to let the server automatically create/update
GZIP/Brotli-compressed versions of compressible static files or not. If set
to <span class="val">Yes</span>, when a file with a
MIME type listed in <span class="tagl"><a
href="#compressibleTypes">Compressible
Types</a></span> is requested, the server may create or update
the corresponding compressed version of the file depending on the
compressed file's timestamp. This compressed file is created under the
<span class="tagl"><a
href="#gzipCacheDir">Static Cache
Directory</a></span>. The filename is based on a MD5 hash of
the path of the original file.<br/><br/> Default value:
Yes</p> <h4>Syntax</h4><p>Select from radio
box</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="gzipStaticCompressLevel"><h3>GZIP Compression Level
(Static File)<span class="ls-permlink"><a
href="#gzipStaticCompressLevel"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the level of GZIP compression applied to static files. Ranges from <span
class="val">1</span> (lowest) to <span
class="val">9</span> (highest).<br/><br/>
This setting will only take effect when <span
class="tagl"><a
href="#enableGzipCompress">Enable
Compression</a></span> and <span
class="tagl"><a
href="#gzipAutoUpdateStatic">Auto Update Static
File</a></span> are enabled.<br/><br/> Default
value: 6</p> <h4>Syntax</h4><p>Number between 1 and
9.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="brStaticCompressLevel"><h3>Brotli Compression Level
(Static File)<span class="ls-permlink"><a
href="#brStaticCompressLevel"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the level of Brotli compression applied to static files. Ranges from
<span class="val">1</span> (lowest) to <span
class="val">11</span> (highest).<br/><br/>
This setting will only take effect when <span
class="tagl"><a
href="#enableGzipCompress">Enable
Compression</a></span> and <span
class="tagl"><a
href="#gzipAutoUpdateStatic">Auto Update Static
File</a></span> are enabled.<br/><br/> Default
value: 5</p> <h4>Syntax</h4><p>Number between 1 and
11.</p> <h4>Tips</h4><p><span
title="Performance"
class="ls-icon-performance"></span> Save network
bandwidth. Text-based responses such as html, css, and javascript files
benefit the most and on average can be compressed to half of their original
size.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="gzipCacheDir"><h3>Static Cache Directory<span
class="ls-permlink"><a
href="#gzipCacheDir"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the path of the directory used to store compressed files for static
content.<br/><br/> Default value: <span
class="tagl"><a href="#swappingDir">Swapping
Directory</a></span>.</p>
<h4>Syntax</h4><p>Directory Path</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="gzipMaxFileSize"><h3>Max Static File Size
(bytes)<span class="ls-permlink"><a
href="#gzipMaxFileSize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the maximum size of a static file for which the server will create a
compressed file automatically.<br/><br/> Default value:
10M</p> <h4>Syntax</h4><p>Number in bytes not less
than 1K.</p> <h4>Tips</h4><p><span
title="Performance"
class="ls-icon-performance"></span> It is not
recommended to have the server create/update compressed files for large
files. Compressing blocks an entire server process and no further requests
can be processed until the compression is completed.</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="gzipMinFileSize"><h3>Min Static File Size
(bytes)<span class="ls-permlink"><a
href="#gzipMinFileSize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the minimum size of a static file for which the server will create a
corresponding compressed file.<br/><br/> Default value:
200</p> <h4>Syntax</h4><p>Number in bytes not less
than 200.</p> <h4>Tips</h4><p><span
title="Information"
class="ls-icon-info"></span> It is not necessary to
compress very small files as the bandwidth saving is negligible.</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sslDefaultCiphers"><h3>Default Cipher Suite<span
class="ls-permlink"><a
href="#sslDefaultCiphers"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Default
cipher suite for SSL certificates.<br/><br/> Default value:
Server Internal Default (Based on current best practices)</p>
<h4>Syntax</h4><p>Colon-separated string of cipher
specifications.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sslStrongDhKey"><h3>SSL Strong DH Key<span
class="ls-permlink"><a
href="#sslStrongDhKey"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
whether to use 2048 or 1024 bit DH keys for SSL handshakes. If set to
"Yes", 2048 bit DH keys will be used for 2048 bit SSL keys and
certificates. 1024 bit DH keys will still be used in other situations.
Default is "Yes".<br/><br/> Earlier versions of Java
do not support DH key size higher than 1024 bits. If Java client
compatibility is required, this should be set to "No".</p>
<h4>Syntax</h4><p>radio</p> </article>
</div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sslEnableMultiCerts"><h3>Enable Multiple SSL
Certificates<span class="ls-permlink"><a
href="#sslEnableMultiCerts"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Allows
listeners/vhosts to set multiple SSL certificates. If multiple
certificates are enabled, the certificates/keys are expected to follow a
naming scheme. If the cert is named server.crt, other possible cert names
are server.crt.rsa, server.crt.dsa, server.crt.ecc. If "Not Set",
defaults to "No".</p>
<h4>Syntax</h4><p>Select from radio box</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sslCertCompress"><h3>Enable Certificate
Compression<span class="ls-permlink"><a
href="#sslCertCompress"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Use
SSL certificate compression.<br/><br/> Default value:
On</p> <h4>Syntax</h4><p>Select from radio
box</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sslHsOffload"><h3>Enable Handshake Offload<span
class="ls-permlink"><a
href="#sslHsOffload"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Offload
SSL handshake to a separate thread.<br/><br/> Default value:
On</p> <h4>Syntax</h4><p>Select from radio
box</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sslSessionCache"><h3>Enable Session Cache<span
class="ls-permlink"><a
href="#sslSessionCache"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Enables
session id caching using OpenSSL's default setting. Default value is
"No".</p> <h4>Syntax</h4><p>Select from
radio box</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sslSessionCacheSize"><h3>Session Cache Size
(bytes)<span class="ls-permlink"><a
href="#sslSessionCacheSize"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Sets
the maximum number of SSL session IDs to store in the cache. Default is
1,000,000.</p> <h4>Syntax</h4><p>Integer
number</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sslSessionCacheTimeout"><h3>Session Cache Timeout
(secs)<span class="ls-permlink"><a
href="#sslSessionCacheTimeout"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>This
value determines how long a session ID will be valid within the cache
before renegotiation is required. Default is 3,600.</p>
<h4>Syntax</h4><p>Integer number</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sslSessionTickets"><h3>Enable Session
Tickets<span class="ls-permlink"><a
href="#sslSessionTickets"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Enables
session tickets using OpenSSL's default session ticket setting.
Server-level setting must be set to "Yes" for Virtual Host
setting to take effect.<br/><br/> Default values:<br/>
<b>Server-level:</b> Yes<br/>
<b>VH-Level:</b> Yes</p>
<h4>Syntax</h4><p>Select from radio box</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sslSessionTicketLifetime"><h3>SSL Session Ticket
Lifetime (secs)<span class="ls-permlink"><a
href="#sslSessionTicketLifetime"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>This
value determines how long a session ticket will be valid before a
renegotiation is required. Default is 3,600.</p>
<h4>Syntax</h4><p>Integer number</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sslSessionTicketKeyFile"><h3>SSL Session Ticket Key
File<span class="ls-permlink"><a
href="#sslSessionTicketKeyFile"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Allows
the SSL Ticket Key to be created/maintained by an administrator. The file
must be 48 bytes long. If this option is left empty, the load balancer will
generate and rotate its own set of keys.<br/><br/> IMPORTANT:
To maintain forward secrecy, it is strongly recommended to change the key
every <b>SSL Session Ticket Lifetime</b> seconds. If this
cannot be done, it is recommended to leave this field empty.</p>
<h4>Syntax</h4><p>Path</p> </article>
</div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sslOcspProxy"><h3>OCSP Proxy<span
class="ls-permlink"><a
href="#sslOcspProxy"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Socket
address used as the proxy server address for OCSP verification. Leave this
setting unset If not using a proxy.<br/><br/> Default value:
<span class="val">not set</span></p>
<h4>Syntax</h4><p>Socket Address</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="sslStrictSni"><h3>Strict SNI Certificate<span
class="ls-permlink"><a
href="#sslStrictSni"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
whether to strictly require a dedicated virtual host certificate
configuration. When enabled, SSL connections to virtual hosts without a
dedicated certificate configuration will fail instead of using a default
catch-all certificate.<br/><br/> Default value: <span
class="val">No</span></p>
<h4>Syntax</h4><p>Select from radio box</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicEnable"><h3>Enable HTTP3/QUIC<span
class="ls-permlink"><a
href="#quicEnable"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Enables
the HTTP3/QUIC network protocol server wide. Default value is <span
class="val">Yes</span>.</p>
<h4>Syntax</h4><p>Select from radio box</p>
<h4>Tips</h4><p><span title="Information"
class="ls-icon-info"></span> When this setting is set to
<span class="val">Yes</span>, HTTP3/QUIC can still be
disabled at the listener level through the <span
class="tagl"><a
href="Listeners_SSL_Help.html#allowQuic">Open HTTP3/QUIC (UDP)
port</a></span> setting, or at the virtual host level through
the <span class="tagl"><a
href="VHSSL_Help.html#vhEnableQuic">Enable
HTTP3/QUIC</a></span> setting.</p> </article>
</div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicShmDir"><h3>QUIC SHM Directory<span
class="ls-permlink"><a
href="#quicShmDir"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the directory used to save QUIC data to shared
memory.<br/><br/> By default, the server's default SHM
directory, <span class="val">/dev/shm</span>, will be
used.</p> <h4>Syntax</h4><p>Path</p>
<h4>Tips</h4><p><span title="Information"
class="ls-icon-info"></span> A RAM based partition, such
as <span class="val">/dev/shm</span>, is
recommended.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicVersions"><h3>HTTP3/QUIC Versions<span
class="ls-permlink"><a
href="#quicVersions"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>A
list of enabled HTTP3/QUIC versions. This setting should only be used to
limit HTTP3/QUIC support to the versions listed and is best left
blank.</p> <h4>Syntax</h4><p>Comma-separated
list</p> <h4>Example</h4><div
class="ls-example">h3-29,
h3-Q050</div><h4>Tips</h4><p><span
title="Information"
class="ls-icon-info"></span> It is recommended to leave
this setting blank to have the the best configuration applied
automatically.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicCongestionCtrl"><h3>Congestion Control<span
class="ls-permlink"><a
href="#quicCongestionCtrl"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>The
congestion control algorithm used. This can be set manually or left up to
the QUIC library in use by selecting the "Default"
option.<br/><br/> Default value: Default</p>
<h4>Syntax</h4><p>Select from drop down list</p>
</article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicCfcw"><h3>Connection Flow Control Window<span
class="ls-permlink"><a
href="#quicCfcw"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>The
initial size of the buffer allocated for a QUIC connection. Default value
is <span class="val">1.5M</span>.</p>
<h4>Syntax</h4><p>Number between 64K and 512M</p>
<h4>Tips</h4><p><span title="Information"
class="ls-icon-info"></span> A larger window size will
use more memory.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicMaxCfcw"><h3>Max Connection Flow Control
Window<span class="ls-permlink"><a
href="#quicMaxCfcw"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the maximum size that a connection flow control window buffer is allowed to
reach due to window auto-tuning.<br/><br/> Default value is
<span class="val">0</span>, which means that the
value of <span class="tagl"><a
href="ServTuning_Help.html#quicCfcw">Connection Flow Control
Window</a></span> is used and no auto-tuning is
performed.</p> <h4>Syntax</h4><p>0 or a number
between 64K and 512M</p> <h4>Tips</h4><p><span
title="Information"
class="ls-icon-info"></span> A larger window size will
use more memory.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicSfcw"><h3>Stream Flow Control Window<span
class="ls-permlink"><a
href="#quicSfcw"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>The
initial amount of data a QUIC connection is willing to receive per stream.
Default value is <span
class="val">1M</span>.</p>
<h4>Syntax</h4><p>Number between 64K and 128M</p>
<h4>Tips</h4><p><span title="Information"
class="ls-icon-info"></span> A larger window size will
use more memory.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicMaxSfcw"><h3>Max Stream Flow Control
Window<span class="ls-permlink"><a
href="#quicMaxSfcw"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Specifies
the maximum size that a stream flow control window is allowed to reach due
to window auto-tuning.<br/><br/> Default value is <span
class="val">0</span>, which means that the value of
<span class="tagl"><a
href="ServTuning_Help.html#quicSfcw">Stream Flow Control
Window</a></span> is used and no auto-tuning is
performed.</p> <h4>Syntax</h4><p>0 or a number
between 64K and 128M</p> <h4>Tips</h4><p><span
title="Information"
class="ls-icon-info"></span> A larger window size will
use more memory.</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicMaxStreams"><h3>Max Concurrent Streams Per
Connection<span class="ls-permlink"><a
href="#quicMaxStreams"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>The
maximum number of concurrent streams allowed per QUIC connection. Default
value is <span class="val">100</span>.</p>
<h4>Syntax</h4><p>Integer number between 10 and
1000</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicHandshakeTimeout"><h3>Handshake Timeout<span
class="ls-permlink"><a
href="#quicHandshakeTimeout"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>The
time in seconds a new QUIC connection is given to complete its handshake,
after which the connection is aborted. Default value is <span
class="val">10</span>.</p>
<h4>Syntax</h4><p>Integer number between 1 and
15</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicIdleTimeout"><h3>Idle Timeout<span
class="ls-permlink"><a
href="#quicIdleTimeout"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>The
time in seconds after which an idle QUIC connection will be closed. Default
value is <span class="val">30</span>.</p>
<h4>Syntax</h4><p>Integer number between 10 and
30</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicEnableDPLPMTUD"><h3>Enable DPLPMTUD<span
class="ls-permlink"><a
href="#quicEnableDPLPMTUD"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>Enable
Datagram Packetization Layer Path Maximum Transmission Unit Discovery
(DPLPMTUD).<br/><br/> <b> <a href="
https://tools.ietf.org/html/rfc8899 " target="_blank"
rel="noopener noreferrer"> Background on DPLPMTUD (RFC
8899) </a> </b><br/><br/> Default value:
Yes</p> <h4>Syntax</h4><p>Select from radio
box</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicBasePLPMTU"><h3>PLPMTU Base Value<span
class="ls-permlink"><a
href="#quicBasePLPMTU"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>The
maximum value of PLPMTU (maximum packet size without headers) in bytes that
QUIC will use by default. Setting this to <span
class="val">0</span> will allow QUIC to pick the
size.<br/><br/> This setting should be set lower than <span
class="tagl"><a href="#quicMaxPLPMTU">PLPMTU
Max Value</a></span>.<br/><br/> Default value:
0</p> <h4>Syntax</h4><p>0 or integer number between
1200 and 65527</p> </article> </div>
<div class="helpitem"><article
class="ls-helpitem"><div><header
id="quicMaxPLPMTU"><h3>PLPMTU Max Value<span
class="ls-permlink"><a
href="#quicMaxPLPMTU"></a></span><span
class="top"><a
href="#top">⇑</a></span></h3></header></div><h4>Description</h4><p>The
PLPMTU (maximum packet size without headers) probe upper limit in bytes.
This setting is used to limit the "maximum packet size" in the
DPLPMTUD search space. Setting this to <span
class="val">0</span> will allow QUIC to pick the size
(By default LSQUIC assumes that MTU is 1,500 bytes
(Ethernet)).<br/><br/> This setting should be set higher than
<span class="tagl"><a
href="#quicBasePLPMTU">PLPMTU Base
Value</a></span>.<br/> Default value: 0</p>
<h4>Syntax</h4><p>0 or integer number between 1200 and
65527</p> </article> </div>
</section>
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