[squid-users] Performance tuning of SMP + Large rock

Hi,

I am using squid cache as a forward caching proxy.

CONTEXT:

For my use case since:
1. the average object size is ~80KB (moreover > 32KB),
2. the proxy server has multiple cores available
3. the throughput requirement is high (upto 1Gbps)

I have configured squid to use SMP + LargeRock. I am using Squid
Cache: Version 3.HEAD-20140127-r13248.

I have configured the cache as:

cache_dir rock /mnt/squid-cache 256000 max-size=4194304
cache_mem 1024 MB

with 4 workers:
workers 4

I am running squid on a VM with 8 vCPUs(reserved cpu) and 8 GB RAM
(reserved). It does not seem to be bottlenecked by cpu or memory
looking at vmstat output.
I get a throughput of ~38MB/sec when all objects are read from cache
(with 64 outstanding parallel HTTPS reads at all times and avg object
size of 80 KB).

QUESTIONS:

1. I am currently using a xfs mount for my cache_dir.
/dev/sdc1 on /mnt/squid-cache type xfs
(rw,noatime,nodiratime,nobarrier,logbufs=8)

What is the recommended filesystem for storing LargeRock database?
Also are there any recommended options that apply to LargeRock? (I
looked through the FAQ and the recommendations there seem to be mainly
for ufs/aufs/diskd which create many small files)

2. Are there any known throughput limits when using SMP + LargeRock?

3. Are there any recommending tuning options that specifically apply
to LargeRock which would help cache read throughput?

Thanks,
Rajiv
Received on Thu Feb 13 2014 - 03:04:13 MST