Re: Performance issue -- serving from cache

Jonathan Lee <[email protected]> Sat, 14 Feb 2026 14:40:49 -0800
Newsgroups gmane.comp.web.squid.general
Message-ID <[email protected]>
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Is it rock cache and how many workers are you using ?
Sent from my iPhone

> On Feb 14, 2026, at 11:45, Brad House <[email protected]> wrote:
>=20
> =EF=BB=BF
> I've got a squid deployment where serving from cache can be slower than an=
 uncached download.  I'm seeing speeds of around 50MB/s when serving from ca=
che, which is much slower than anticipated.  Infact, when hitting fast upstr=
eam servers, serving of a non-cached asset is faster (even though its still h=
itting squid to fetch it). =20
>=20
> I'm thinking there's got to be something wrong with my squid configuration=
, I'm currently running on Rocky Linux 10 with Squid 6.10-6.
>=20
> The VM I'm using currently has 4 cores, 16G RAM and 100G of usable space. =
 I used fio to measure disk performance and I got=20
>=20
> Random Write: 3629MiB/s (1MB block), 33.2k (4k block) IOPS
> Random Read: 8391MiB/s (1MB block), 43.5k (4k block) IOPS
> Adding more cpu cores or ram doesn't appear to impact performance.
>=20
> The underlying infrastructure is made up of hypervisors with dual 100G upl=
inks, both the client and squid run on the same hypervisor cloud.  Network p=
erformance is not the issue.
>=20
> As a test, I spun up Apache Traffic Server and get over 800MB/s when servi=
ng from cache.
>=20
> We have a large on site build system that spins up runners for GitHub acti=
ons, and they're constantly fetching large assets from the internet for each=
 build, hence our desire for a caching proxy.  We'd rather not switch to Apa=
che Traffic Server as that doesn't have SSL bump capability (we haven't yet e=
nabled that capability in squid, however).  Hopefully there's a simple confi=
guration I'm missing.
>=20
> Just for testing I was pulling large image via http that is below my max o=
bject size: http://mirrors.edge.kernel.org/ubuntu-releases/20.04.6/ubuntu-20=
.04.6-live-server-amd64.iso
>=20
> Configuration below:
>=20
> acl public src 0.0.0.0/0
> acl SSL_ports port 443
> acl Safe_ports port 80
> acl Safe_ports port 443
> http_access deny !Safe_ports
> http_access deny CONNECT !SSL_ports
> http_access allow localhost manager
> http_access deny manager
> http_access allow public
> http_access deny to_localhost
> http_access deny to_linklocal
> http_access deny all
> http_port 8080
> maximum_object_size 2 GB
> cache_dir aufs /var/spool/squid 325632 16 256
> cache_mem 1000 MB
> maximum_object_size_in_memory 102400 KB
> coredump_dir /var/spool/squid
> refresh_pattern -i (/cgi-bin/|\?) 0    0%    0
> refresh_pattern deb$   129600 100% 129600
> refresh_pattern udeb$   129600 100% 129600
> refresh_pattern tar.gz$  129600 100% 129600
> refresh_pattern tar.xz$  129600 100% 129600
> refresh_pattern tar.bz2$  129600 100% 129600
> refresh_pattern \/(Packages|Sources)(|\.bz2|\.gz|\.xz)$ 0 0% 0 refresh-ims=

> refresh_pattern \/Release(|\.gpg)$ 0 0% 0 refresh-ims
> refresh_pattern \/InRelease$ 0 0% 0 refresh-ims
> refresh_pattern \/(Translation-.*)(|\.bz2|\.gz|\.xz)$ 0 0% 0 refresh-ims
> refresh_pattern changelogs.ubuntu.com\/.*  0  1% 1
>=20
>=20
>=20
> Thanks!
>=20
> -Brad
>=20
> _______________________________________________
> squid-users mailing list
> [email protected]
> https://lists.squid-cache.org/listinfo/squid-users

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<html class=3D"apple-mail-supports-explicit-dark-mode"><head><meta http-equi=
v=3D"content-type" content=3D"text/html; charset=3Dutf-8"></head><body dir=3D=
"auto">Is it rock cache and how many workers are you using ?<br id=3D"lineBr=
eakAtBeginningOfSignature"><div dir=3D"ltr">Sent from my iPhone</div><div di=
r=3D"ltr"><br><blockquote type=3D"cite">On Feb 14, 2026, at 11:45, Brad Hous=
e &lt;[email protected]&gt; wrote:<br><br></blockquote></div><blockquote t=
ype=3D"cite"><div dir=3D"ltr">=EF=BB=BF

 =20

    <meta http-equiv=3D"content-type" content=3D"text/html; charset=3DUTF-8"=
>
 =20
 =20
    <p>I've got a squid deployment where serving from cache can be
      slower than an uncached download.&nbsp; I'm seeing speeds of around
      50MB/s when serving from cache, which is much slower than
      anticipated.&nbsp; Infact, when hitting fast upstream servers, serving=

      of a non-cached asset is faster (even though its still hitting
      squid to fetch it).&nbsp;&nbsp;</p>
    <p>I'm thinking there's got to be something wrong with my squid
      configuration, I'm currently running on Rocky Linux 10 with Squid
      6.10-6.</p>
    <p>The VM I'm using currently has 4 cores, 16G RAM and 100G of
      usable space.&nbsp; I used fio to measure disk performance and I got&n=
bsp;</p>
    <ul data-list-tree=3D"true" data-indent=3D"1" data-border=3D"0" style=3D=
"margin: 4px 0 4px 24px; padding: 0; list-style-position: outside">
      <li style=3D"margin: 2px 0; padding: 0; color: #1d1c1d">Random
        Write: 3629MiB/s (1MB block), 33.2k (4k block) IOPS</li>
      <li style=3D"margin: 2px 0; padding: 0; color: #1d1c1d">Random Read:
        8391MiB/s&nbsp;(1MB block), 43.5k (4k block) IOPS</li>
    </ul>
    <p>Adding more cpu cores or ram doesn't appear to impact
      performance.</p>
    <p>The underlying infrastructure is made up of hypervisors with dual
      100G uplinks, both the client and squid run on the same hypervisor
      cloud.&nbsp; Network performance is not the issue.</p>
    <p>As a test, I spun up Apache Traffic Server and get over 800MB/s
      when serving from cache.</p>
    <p>We have a large on site build system that spins up runners for
      GitHub actions, and they're constantly fetching large assets from
      the internet for each build, hence our desire for a caching
      proxy.&nbsp; We'd rather not switch to Apache Traffic Server as that
      doesn't have SSL bump capability (we haven't yet enabled that
      capability in squid, however).&nbsp; Hopefully there's a simple
      configuration I'm missing.</p>
    <p>Just for testing I was pulling large image via http that is below
      my max object size:
<a class=3D"moz-txt-link-freetext" href=3D"http://mirrors.edge.kernel.org/ub=
untu-releases/20.04.6/ubuntu-20.04.6-live-server-amd64.iso">http://mirrors.e=
dge.kernel.org/ubuntu-releases/20.04.6/ubuntu-20.04.6-live-server-amd64.iso<=
/a></p>
    <p>Configuration below:</p>
    <p>acl public src 0.0.0.0/0<br>
      acl SSL_ports port 443<br>
      acl Safe_ports port 80<br>
      acl Safe_ports port 443<br>
      http_access deny !Safe_ports<br>
      http_access deny CONNECT !SSL_ports<br>
      http_access allow localhost manager<br>
      http_access deny manager<br>
      http_access allow public<br>
      http_access deny to_localhost<br>
      http_access deny to_linklocal<br>
      http_access deny all<br>
      http_port 8080<br>
      maximum_object_size 2 GB<br>
      cache_dir aufs /var/spool/squid 325632 16 256<br>
      cache_mem 1000 MB<br>
      maximum_object_size_in_memory 102400 KB<br>
      coredump_dir /var/spool/squid<br>
      refresh_pattern -i (/cgi-bin/|\?) 0&nbsp; &nbsp; 0%&nbsp; &nbsp; 0<br>=

      refresh_pattern deb$&nbsp; &nbsp;129600 100% 129600<br>
      refresh_pattern udeb$&nbsp; &nbsp;129600 100% 129600<br>
      refresh_pattern tar.gz$&nbsp; 129600 100% 129600<br>
      refresh_pattern tar.xz$&nbsp; 129600 100% 129600<br>
      refresh_pattern tar.bz2$&nbsp; 129600 100% 129600<br>
      refresh_pattern \/(Packages|Sources)(|\.bz2|\.gz|\.xz)$ 0 0% 0
      refresh-ims<br>
      refresh_pattern \/Release(|\.gpg)$ 0 0% 0 refresh-ims<br>
      refresh_pattern \/InRelease$ 0 0% 0 refresh-ims<br>
      refresh_pattern \/(Translation-.*)(|\.bz2|\.gz|\.xz)$ 0 0% 0
      refresh-ims<br>
      refresh_pattern changelogs.ubuntu.com\/.*&nbsp; 0&nbsp; 1% 1</p>
    <p><br>
    </p>
    <p>Thanks!</p>
    <p>-Brad</p>
 =20

<span>_______________________________________________</span><br><span>squid-=
users mailing list</span><br><span>[email protected]</span><=
br><span>https://lists.squid-cache.org/listinfo/squid-users</span><br></div>=
</blockquote></body></html>=

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