[squid-users] Squid 3-5 CPU optimization and best practise .

[Alex Rousskov]

On 3/31/22 11:04, Ahmad Alzaeem wrote:

> My main question is , is there any major changes in squid 5 that make it 
> faster than squid 3 or squid 4 in terms of low CPU usage?

I do not recall any _major_ changes in that area, but the http_port 
worker-queues option may be of interest to those looking for performance 
optimizations.


> Is there any best practice I can use to lower the cpu usage or response 
> time ?

YMMV, but I would start by using (the right number of) SMP workers with 
cpu_affinity_map and worker-queues. More on that at
https://wiki.squid-cache.org/Features/SmpScale#How_to_configure_SMP_Squid_for_top_performance.3F

Beyond that, one would have to analyze your Squid performance to find 
out performance bottleneck(s) and then try to eliminate them or reduce 
their impact.


> Like Deny caching on the HDD or server_persistent_connections off 
>   similar directives

Disabling persistent connections will make things _worse_ in many cases 
but YMMV. Whether cache_dirs (and even shared memory cache) slow down or 
speed up an average response depends on your environment -- measure and 
adjust/remove accordingly.


HTH,

Alex.