Re: [squid-users] Slower from cache??

ufs beats both aufs and diskd on underutilized caches, but quickly
spirals down when you start giving it some load. usually the
cutoffpoint is about 30 requests/second.

Above this cuttoff point (which is very sharp once you hit it) ufs
becomes completely unusable buf aufs and diskd keeps on doing their
job until other bottlenecks is reached.

It is also the case that both aufs and diskd needs to have some
concurrent sessions in order to yield good performance. On idle
caches the idletime may cause both diskd and aufs to stall waiting
for some activity, further delaying the request.. One can say they
get bored if not having things to do ;-)

Regards
Henrik

On Friday 14 June 2002 23:20, Peter Smith wrote:
> Interesting, I switched the cache-access type to 'ufs' and
> everything seems great. 'aufs' is just as slow as 'diskd'...
>
> Peter Smith wrote:
> > I recently stumbled across this behavior on one of my proxys.
> > This is a test proxy and is not used often. I proxy an ftp file
> > of considerable size and everything goes as planned. However,
> > getting the file from the cache appears slower than the original
> > internet-based download. Btw, I am lucky in that I am on
> > Internet2, so ~2.5MB/s is normal. I don't see how I could
> > possibly be misconfigured. During this whole test the proxy is
> > practically asleep it is so underutilised. Is there anything I
> > should look at? I also don't see how it could be my hardware
> > and/or software. It just looks like Squid is not functioning
> > well.
> >
> > [root@client tmp]# time ftp_proxy=proxy:3128 wget
> > ftp://ftp.ttu.edu/pub/mirrors/kernel.org/linux/kernel/v2.4/linux-
> >2.4.18.tar.gz
> >
> > --04:59:02--
> > ftp://ftp.ttu.edu/pub/mirrors/kernel.org/linux/kernel/v2.4/linux-
> >2.4.18.tar.gz
> >
> > => `linux-2.4.18.tar.gz.6'
> > Connecting to proxy:3128... connected!
> > Proxy request sent, awaiting response... 200 OK
> > Length: 30,108,170 [application/x-tar]
> >
> > 0K .......... .......... .......... .......... .......... 0%
> > @ 531.91 KB/s
> > 50K .......... .......... .......... .......... .......... 0%
> > @ 1.74 MB/s
> > 100K .......... .......... .......... .......... .......... 0%
> > @ 2.22 MB/s
> > 150K .......... .......... .......... .......... .......... 0%
> > @ 2.22 MB/s
> > 200K .......... .......... .......... .......... .......... 0%
> > @ 2.22 MB/s
> > ...
> > 29200K .......... .......... .......... .......... .......... 99%
> > @ 3.05 MB/s
> > 29250K .......... .......... .......... .......... .......... 99%
> > @ 2.33 MB/s
> > 29300K .......... .......... .......... .......... .......... 99%
> > @ 2.44 MB/s
> > 29350K .......... .......... .......... .......... .......... 99%
> > @ 2.44 MB/s
> > 29400K .. 100%
> > @ 76.05 KB/s
> >
> > 04:59:14 (2.41 MB/s) - `linux-2.4.18.tar.gz.6' saved
> > [30108170/30108170]
> >
> >
> > real 0m12.349s
> > user 0m0.150s
> > sys 0m0.680s
> >
> > -------------------------
> > 1024070757.154 12341 proxy TCP_MISS/200 30108463 GET
> > ftp://ftp.ttu.edu/pub/mirrors/kernel.org/linux/kernel/v2.4/linux-
> >2.4.18.tar.gz - DIRECT/129.118.2.10 application/x-tar
> > -------------------------
> > [root@client tmp]# time ftp_proxy=proxy:3128 wget
> > ftp://ftp.ttu.edu/pub/mirrors/kernel.org/linux/kernel/v2.4/linux-
> >2.4.18.tar.gz
> >
> > --04:59:24--
> > ftp://ftp.ttu.edu/pub/mirrors/kernel.org/linux/kernel/v2.4/linux-
> >2.4.18.tar.gz
> >
> > => `linux-2.4.18.tar.gz.7'
> > Connecting to proxy:3128... connected!
> > Proxy request sent, awaiting response... 200 OK
> > Length: 30,108,170 [application/x-tar]
> >
> > 0K .......... .......... .......... .......... .......... 0%
> > @ 209.21 KB/s
> > 50K .......... .......... .......... .......... .......... 0%
> > @ 191.57 KB/s
> > 100K .......... .......... .......... .......... .......... 0%
> > @ 227.27 KB/s
> > 150K .......... .......... .......... .......... .......... 0%
> > @ 192.31 KB/s
> > 200K .......... .......... .......... .......... .......... 0%
> > @ 209.21 KB/s
> > ...
> > 29200K .......... .......... .......... .......... .......... 99%
> > @ 207.47 KB/s
> > 29250K .......... .......... .......... .......... .......... 99%
> > @ 193.05 KB/s
> > 29300K .......... .......... .......... .......... .......... 99%
> > @ 248.76 KB/s
> > 29350K .......... .......... .......... .......... .......... 99%
> > @ 9.77 MB/s
> > 29400K .. 100%
> > @ 2.45 MB/s
> >
> > 05:01:26 (241.42 KB/s) - `linux-2.4.18.tar.gz.7' saved
> > [30108170/30108170]
> >
> >
> > real 2m1.816s
> > user 0m0.130s
> > sys 0m0.290s
> >
> > -------------------------
> > 1024070888.819 121808 proxy TCP_HIT/200 30108471 GET
> > ftp://ftp.ttu.edu/pub/mirrors/kernel.org/linux/kernel/v2.4/linux-
> >2.4.18.tar.gz - NONE/- application/x-tar
> > -------------------------
> > [root@proxy root]# squid -v
> > Squid Cache: Version 2.4.STABLE3
> > -------------------------
> > hierarchy_stoplist cgi-bin ?
> > acl QUERY urlpath_regex cgi-bin \?
> > no_cache deny QUERY
> >
> > acl virus1 urlpath_regex /readme\.exe$
> > http_access deny virus1
> >
> > acl virus2a dstdomain us.f1.yahoofs.com
> > acl virus2b urlpath_regex /timeupdate\.exe$
> > http_access deny virus2a virus2b
> >
> > acl virus3 urlpath_regex /explorer\.exe$
> > http_access deny virus3
> >
> > acl all src 0.0.0.0/0.0.0.0
> > acl CONNECT method CONNECT
> > http_access allow all
> >
> > # SNMP:
> > acl snmppublic snmp_community XXXX
> > snmp_access allow snmppublic
> > snmp_access deny all
> >
> > # Timeouts:
> > read_timeout 5 minutes
> > request_timeout 30 seconds
> > pconn_timeout 60 seconds
> > half_closed_clients on
> > shutdown_lifetime 0 seconds
> > negative_ttl 30 seconds
> > icp_query_timeout 1000 milliseconds
> > reference_age 1 week
> >
> > cache_effective_user squid
> > cache_effective_group squid
> > cache_dir diskd /cache1 4096 64 64 Q1=72 Q2=64
> > cache_dir diskd /cache2 4096 64 64 Q1=72 Q2=64
> > cache_dir diskd /cache3 4096 64 64 Q1=72 Q2=64
> > cache_mem 400 MB
> >
> > maximum_object_size 256 MB
> > minimum_object_size 0
> > request_body_max_size 0
> > request_header_max_size 64 KB
> >
> > announce_host localhost
> > visible_hostname proxy
> > http_port 3128
> > cache_store_log none
> > fqdncache_size 0
Received on Fri Jun 14 2002 - 18:45:36 MDT