<!DOCTYPE html><htmllang="en"><head><metacharset="utf-8"><metaname="viewport"content="width=device-width, initial-scale=1.0"><metaname="generator"content="rustdoc"><metaname="description"content="The maximum number of pending connections."><metaname="keywords"content="rust, rustlang, rust-lang, Backlog"><title>Backlog in actix_settings - Rust</title><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../SourceSerif4-Regular.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../FiraSans-Regular.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../FiraSans-Medium.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../SourceCodePro-Regular.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../SourceSerif4-Bold.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../SourceCodePro-Semibold.ttf.woff2"><linkrel="stylesheet"href="../normalize.css"><linkrel="stylesheet"href="../rustdoc.css"id="mainThemeStyle"><linkrel="stylesheet"href="../ayu.css"disabled><linkrel="stylesheet"href="../dark.css"disabled><linkrel="stylesheet"href="../light.css"id="themeStyle"><scriptid="default-settings"></script><scriptsrc="../storage.js"></script><scriptdefersrc="sidebar-items.js"></script><scriptdefersrc="../main.js"></script><noscript><linkrel="stylesheet"href="../noscript.css"></noscript><linkrel="icon"href="https://actix.rs/favicon.ico"></head><bodyclass="rustdoc enum"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><navclass="mobile-topbar"><buttonclass="sidebar-menu-toggle">☰</button><aclass="sidebar-logo"href="../actix_settings/index.html"><divclass="logo-container"><imgsrc="https://actix.rs/img/logo.png"alt="logo"></div></a><h2class="location"></h2></nav><navclass="sidebar"><aclass="sidebar-logo"href="../actix_settings/index.html"><divclass="logo-container">
<imgsrc="https://actix.rs/img/logo.png"alt="logo"></a><navclass="sub"><formclass="search-form"><divclass="search-container"><span></span><inputclass="search-input"name="search"autocomplete="off"spellcheck="false"placeholder="Click or press ‘S’ to search, ‘?’ for more options…"type="search"><divid="help-button"title="help"tabindex="-1"><buttontype="button">?</button></div><divid="settings-menu"tabindex="-1"><ahref="../settings.html"title="settings"><imgwidth="22"height="22"alt="Change settings"src="../wheel.svg"></a></div></div></form></nav></div><sectionid="main-content"class="content"><divclass="main-heading"><h1class="fqn"><spanclass="in-band">Enum <ahref="index.html">actix_settings</a>::<wbr><aclass="enum"href="#">Backlog</a><buttonid="copy-path"onclick="copy_path(this)"title="Copy item path to clipboard"><imgsrc="../clipboard.svg"width="19"height="18"alt="Copy item path"></button></span></h1><spanclass="out-of-band"><aclass="srclink"href="../src/actix_settings/settings/backlog.rs.html#16-22">source</a> · <aid="toggle-all-docs"href="javascript:void(0)"title="collapse all docs">[<spanclass="inner">−</span>]</a></span></div><divclass="item-decl"><preclass="rust enum"><code>pub enum Backlog {
}</code></pre></div><detailsclass="rustdoc-toggle top-doc"open><summaryclass="hideme"><span>Expand description</span></summary><divclass="docblock"><p>The maximum number of pending connections.</p>
<p>This refers to the number of clients that can be waiting to be served. Exceeding this number
results in the client getting an error when attempting to connect. It should only affect servers
under significant load.</p>
<p>Generally set in the 64–2048 range. The default value is 2048. Takes a string value: Either
“default”, or an integer N > 0 e.g. “6”.</p>
</div></details><h2id="variants"class="variants small-section-header">Variants<ahref="#variants"class="anchor"></a></h2><h3id="variant.Default"class="variant small-section-header"><ahref="#variant.Default"class="anchor field"></a><code>Default</code></h3><divclass="docblock"><p>The default number of connections. See struct docs.</p>
</div><h3id="variant.Manual"class="variant small-section-header"><ahref="#variant.Manual"class="anchor field"></a><code>Manual(<aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.usize.html">usize</a>)</code></h3><divclass="docblock"><p>A specific number of connections.</p>
</div><h2id="trait-implementations"class="small-section-header">Trait Implementations<ahref="#trait-implementations"class="anchor"></a></h2><divid="trait-implementations-list"><detailsclass="rustdoc-toggle implementors-toggle"open><summary><sectionid="impl-Clone-for-Backlog"class="impl has-srclink"><aclass="srclink rightside"href="../src/actix_settings/settings/backlog.rs.html#15">source</a><ahref="#impl-Clone-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl <aclass="trait"href="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html"title="trait core::clone::Clone">Clone</a> for <aclass="enum"href="enum.Backlog.html"title="enum actix_settings::Backlog">Backlog</a></h3></section></summary><divclass="impl-items"><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.clone"class="method trait-impl has-srclink"><aclass="srclink rightside"href="../src/actix_settings/settings/backlog.rs.html#15">source</a><ahref="#method.clone"class="anchor"></a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#tymethod.clone"class="fnname">clone</a>(&self) -><aclass="enum"href="enum.Backlog.html"title="enum actix_settings::Backlog">Backlog</a></h4></section></summary><divclass='docblock'>Returns a copy of the value. <ahref="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#tymethod.clone">Read more</a></div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.clone_from"class="method trait-impl has-srclink"><spanclass="rightside"><spanclass="since"title="Stable since Rust version 1.0.0">1.0.0</span> · <aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/clone.rs.html#132-134">source</a></span><ahref="#method.clone_from"class="anchor"></a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#method.clone_from"class="fnname">clone_from</a>(&mut self, source: <aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&</a>Self)</h4></section></summary><divclass='docblock'>Performs copy-assignment from <code>source</code>. <ahref="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#method.clone_from">Read more</a></div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"open><summary><sectionid="impl-Debug-for-Backlog"class="impl has-srclink"><aclass="srclink rightside"href="../src/actix_settings/settings/backlog.rs.html#15">source</a><ahref="#impl-Debug-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl <aclass="trait"href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html"title="trait core::fmt::Debug">Debug</a> for <aclass="enum"href="enum.Backlog.html"title="enum actix_settings::Backlog">Backlog</a></h3></section></summary><divclass="impl-items"><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.fmt"class="method trait-impl has-srclink"><aclass="srclink rightside"href="../src/actix_settings/settings/backlog.rs.html#15">source</a><ahref="#method.fmt"class="anchor"></a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt"class="fnname">fmt</a>(&self, f: &mut <aclass="struct"href="https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html"title="struct core::fmt::Formatter">Formatter</a><'_>) -><aclass="type"href="https://doc.rust-lang.org/nightly/core/fmt/type.Result.html"title="type core::fmt::Result">Result</a></h4></section></summary><divclass='docblock'>Formats the value using the given formatter. <ahref="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"open><summary><sectionid="impl-Deserialize%3C%27de%3E-for-Backlog"class="impl has-srclink"><aclass="srclink rightside"href="../src/actix_settings/settings/backlog.rs.html#39-70">so
by <code>==</code>. <ahref="https://doc.rust-lang.org/nightly/core/cmp/trait.PartialEq.html#tymethod.eq">Read more</a></div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.ne"class="method trait-impl has-srclink"><spanclass="rightside"><spanclass="since"title="Stable since Rust version 1.0.0">1.0.0</span> · <aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/cmp.rs.html#236">source</a></span><ahref="#method.ne"class="anchor"></a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/nightly/core/cmp/trait.PartialEq.html#method.ne"class="fnname">ne</a>(&self, other: <aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&</a>Rhs) -><aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.bool.html">bool</a></h4></section></summary><divclass='docblock'>This method tests for <code>!=</code>. The default implementation is almost always
sufficient, and should not be overridden without very good reason. <ahref="https://doc.rust-lang.org/nightly/core/cmp/trait.PartialEq.html#method.ne">Read more</a></div></details></div></details><sectionid="impl-Eq-for-Backlog"class="impl has-srclink"><aclass="srclink rightside"href="../src/actix_settings/settings/backlog.rs.html#15">source</a><ahref="#impl-Eq-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl <aclass="trait"href="https://doc.rust-lang.org/nightly/core/cmp/trait.Eq.html"title="trait core::cmp::Eq">Eq</a> for <aclass="enum"href="enum.Backlog.html"title="enum actix_settings::Backlog">Backlog</a></h3></section><sectionid="impl-StructuralEq-for-Backlog"class="impl has-srclink"><aclass="srclink rightside"href="../src/actix_settings/settings/backlog.rs.html#15">source</a><ahref="#impl-StructuralEq-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl <aclass="trait"href="https://doc.rust-lang.org/nightly/core/marker/trait.StructuralEq.html"title="trait core::marker::StructuralEq">StructuralEq</a> for <aclass="enum"href="enum.Backlog.html"title="enum actix_settings::Backlog">Backlog</a></h3></section><sectionid="impl-StructuralPartialEq-for-Backlog"class="impl has-srclink"><aclass="srclink rightside"href="../src/actix_settings/settings/backlog.rs.html#15">source</a><ahref="#impl-StructuralPartialEq-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl <aclass="trait"href="https://doc.rust-lang.org/nightly/core/marker/trait.StructuralPartialEq.html"title="trait core::marker::StructuralPartialEq">StructuralPartialEq</a> for <aclass="enum"href="enum.Backlog.html"title="enum actix_settings::Backlog">Backlog</a></h3></section></div><h2id="synthetic-implementations"class="small-section-header">Auto Trait Implementations<ahref="#synthetic-implementations"class="anchor"></a></h2><divid="synthetic-implementations-list"><sectionid="impl-RefUnwindSafe-for-Backlog"class="impl has-srclink"><ahref="#impl-RefUnwindSafe-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl <aclass="trait"href="https://doc.rust-lang.org/nightly/core/panic/unwind_safe/trait.RefUnwindSafe.html"title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a> for <aclass="enum"href="enum.Backlog.html"title="enum actix_settings::Backlog">Backlog</a></h3></section><sectionid="impl-Send-for-Backlog"class="impl has-srclink"><ahref="#impl-Send-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl <aclass="trait"href="https://doc.rust-lang.org/nightly/core/marker/trait.Send.html"title="trait core::marker::Send">Send</a> for <aclass="enum"href="enum.Backlog.html"title="enum actix_settings::Backlog">Backlog</a></h3></section><sectionid="impl-Sync-for-Backlog"class="impl has-srclink"><ahref="#impl-Sync-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl <aclass="trait"href="https://doc.rust-lang.org/nightly/core/marker/trait.Sync.html"title="trait core::marker::Sync">Sync</a> for <aclass="enum"href="enum.Backlog.html"title="enum actix_settings::Backlog">Backlog</a></h3></section><sectionid="impl-Unpin-for-Backlog"class="impl has-srclink"><ahref="#impl-Unpin-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl <aclass="trait"href="https://doc.rust-lang.org/nightly/core/marker/trait.Unpin.html"title="trait core::marker::Unpin">Unpin</a> for <aclass="enum"href="enum.Backlog.html"title="enum actix_settings::Backlog">Backlog</a></h3></section><sectionid="impl-UnwindSafe-for-Backlog"class="impl has-srclink"><ahref="#impl-UnwindSafe-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl <aclass="trait"href="https://doc.rust-lang.org/nightly/core/panic/unwind_safe/trait.UnwindSafe.html"title="trait core::panic::unwind_safe::UnwindSafe">UnwindSafe</a> for <aclass="enum"href="enum.Backlog.html"title="enum actix_settings::Backlog">Backlog</a></h3></section></div><h2id="blanket-implementations"class="small-section-header">Blanket Implementations<ahref="
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"><summary><sectionid="impl-Instrument-for-Backlog"class="impl has-srclink"><aclass="srclink rightside"href="https://docs.rs/tracing/0.1.36/src/tracing/instrument.rs.html#276">source</a><ahref="#impl-Instrument-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://docs.rs/tracing/0.1.36/tracing/instrument/trait.Instrument.html"title="trait tracing::instrument::Instrument">Instrument</a> for T</h3></section></summary><divclass="impl-items"><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.instrument"class="method trait-impl has-srclink"><aclass="srclink rightside"href="https://docs.rs/tracing/0.1.36/src/tracing/instrument.rs.html#82">source</a><ahref="#method.instrument"class="anchor"></a><h4class="code-header">fn <ahref="https://docs.rs/tracing/0.1.36/tracing/instrument/trait.Instrument.html#method.instrument"class="fnname">instrument</a>(self, span: <aclass="struct"href="https://docs.rs/tracing/0.1.36/tracing/span/struct.Span.html"title="struct tracing::span::Span">Span</a>) -><aclass="struct"href="https://docs.rs/tracing/0.1.36/tracing/instrument/struct.Instrumented.html"title="struct tracing::instrument::Instrumented">Instrumented</a><Self></h4></section></summary><divclass='docblock'>Instruments this type with the provided <ahref="https://docs.rs/tracing/0.1.36/tracing/span/struct.Span.html"title="Span"><code>Span</code></a>, returning an
<code>Instrumented</code> wrapper. <ahref="https://docs.rs/tracing/0.1.36/tracing/instrument/trait.Instrument.html#method.instrument">Read more</a></div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.in_current_span"class="method trait-impl has-srclink"><aclass="srclink rightside"href="https://docs.rs/tracing/0.1.36/src/tracing/instrument.rs.html#121">source</a><ahref="#method.in_current_span"class="anchor"></a><h4class="code-header">fn <ahref="https://docs.rs/tracing/0.1.36/tracing/instrument/trait.Instrument.html#method.in_current_span"class="fnname">in_current_span</a>(self) -><aclass="struct"href="https://docs.rs/tracing/0.1.36/tracing/instrument/struct.Instrumented.html"title="struct tracing::instrument::Instrumented">Instrumented</a><Self></h4></section></summary><divclass='docblock'>Instruments this type with the <ahref="https://docs.rs/tracing/0.1.36/tracing/span/struct.Span.html#method.current">current</a><ahref="https://docs.rs/tracing/0.1.36/tracing/span/struct.Span.html"><code>Span</code></a>, returning an
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"><summary><sectionid="impl-Same%3CT%3E-for-Backlog"class="impl has-srclink"><aclass="srclink rightside"href="https://docs.rs/typenum/1.15.0/src/typenum/type_operators.rs.html#34">source</a><ahref="#impl-Same%3CT%3E-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://docs.rs/typenum/1.15.0/typenum/type_operators/trait.Same.html"title="trait typenum::type_operators::Same">Same</a><T> for T</h3></section></summary><divclass="impl-items"><detailsclass="rustdoc-toggle"open><summary><sectionid="associatedtype.Output"class="associatedtype trait-impl has-srclink"><ahref="#associatedtype.Output"class="anchor"></a><h4class="code-header">type <ahref="https://docs.rs/typenum/1.15.0/typenum/type_operators/trait.Same.html#associatedtype.Output"class="associatedtype">Output</a> = T</h4></section></summary><divclass='docblock'>Should always be <code>Self</code></div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"><summary><sectionid="impl-ToOwned-for-Backlog"class="impl has-srclink"><aclass="srclink rightside"href="https://doc.rust-lang.org/nightly/src/alloc/borrow.rs.html#83">source</a><ahref="#impl-ToOwned-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://doc.rust-lang.org/nightly/alloc/borrow/trait.ToOwned.html"title="trait alloc::borrow::ToOwned">ToOwned</a> for T<spanclass="where fmt-newline">where<br> T: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html"title="trait core::clone::Clone">Clone</a>,</span></h3></section></summary><divclass="impl-items"><detailsclass="rustdoc-toggle"open><summary><sectionid="associatedtype.Owned"class="associatedtype trait-impl has-srclink"><ahref="#associatedtype.Owned"class="anchor"></a><h4class="code-header">type <ahref="https://doc.rust-lang.org/nightly/alloc/borrow/trait.ToOwned.html#associatedtype.Owned"class="associatedtype">Owned</a> = T</h4></section></summary><divclass='docblock'>The resulting type after obtaining ownership.</div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.to_owned"class="method trait-impl has-srclink"><aclass="srclink rightside"href="https://doc.rust-lang.org/nightly/src/alloc/borrow.rs.html#88">source</a><ahref="#method.to_owned"class="anchor"></a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/nightly/alloc/borrow/trait.ToOwned.html#tymethod.to_owned"class="fnname">to_owned</a>(&self) -> T</h4></section></summary><divclass='docblock'>Creates owned data from borrowed data, usually by cloning. <ahref="https://doc.rust-lang.org/nightly/alloc/borrow/trait.ToOwned.html#tymethod.to_owned">Read more</a></div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.clone_into"class="method trait-impl has-srclink"><aclass="srclink rightside"href="https://doc.rust-lang.org/nightly/src/alloc/borrow.rs.html#92">source</a><ahref="#method.clone_into"class="anchor"></a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/nightly/alloc/borrow/trait.ToOwned.html#method.clone_into"class="fnname">clone_into</a>(&self, target: <aclass="primitive"href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&mut </a>T)</h4></section></summary><divclass='docblock'>Uses borrowed data to replace owned data, usually by cloning. <ahref="https://doc.rust-lang.org/nightly/alloc/borrow/trait.ToOwned.html#method.clone_into">Read more</a></div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"><summary><sectionid="impl-TryFrom%3CU%3E-for-Backlog"class="impl has-srclink"><aclass="srclink rightside"href="https://doc.rust-lang.org/nightly/src/core/convert/mod.rs.html#601">source</a><ahref="#impl-TryFrom%3CU%3E-for-Backlog"class="anchor"></a><h3class="code-header in-band">impl<T, U><aclass="trait"hre
<ahref="https://docs.rs/tracing/0.1.36/tracing/instrument/struct.WithDispatch.html"title="WithDispatch"><code>WithDispatch</code></a> wrapper. <ahref="https://docs.rs/tracing/0.1.36/tracing/instrument/trait.WithSubscriber.html#method.with_subscriber">Read more</a></div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.with_current_subscriber"class="method trait-impl has-srclink"><aclass="srclink rightside"href="https://docs.rs/tracing/0.1.36/src/tracing/instrument.rs.html#221">source</a><ahref="#method.with_current_subscriber"class="anchor"></a><h4class="code-header">fn <ahref="https://docs.rs/tracing/0.1.36/tracing/instrument/trait.WithSubscriber.html#method.with_current_subscriber"class="fnname">with_current_subscriber</a>(self) -><aclass="struct"href="https://docs.rs/tracing/0.1.36/tracing/instrument/struct.WithDispatch.html"title="struct tracing::instrument::WithDispatch">WithDispatch</a><Self></h4></section></summary><divclass='docblock'>Attaches the current <ahref="https://docs.rs/tracing/0.1.36/tracing/dispatcher/index.html#setting-the-default-subscriber">default</a><ahref="https://docs.rs/tracing-core/0.1.22/tracing_core/subscriber/trait.Subscriber.html"><code>Subscriber</code></a> to this type, returning a
