cache manager process - i/o perf

[Maxim Dounin]

Hello!

On Wed, May 21, 2014 at 07:57:00AM -0400, ixos wrote:

> I'm having problem with I/O performance. I'm running nginx as caching
> reverse proxy server.
> When cache size on disk exceeds max_size cache manager starts working, but
> it causes two problems occur:
> 
> 1) I/O %util reach 100% and nginx starts dropping connections
> 2) cache manager process dosen't unlink files speed enough to delete old
> file. So cache becomes bigger util the space on disk ends.
> 
> Can you give me an idea how can I solve those problems. Below are some
> details.
> 
> #build on 20x 300GB SAS disks with 2 SSDs for Cachecade.

[...]

> # grep proxy_cache_path nginx.conf
> proxy_cache_path /cache zone=my-cache:20000msize=3355443m

The "proxy_cache_path" looks corrupted and incomplete.  First of 
all, I would suggest you to make sure you are using "levels" 
parameter, see http://nginx.org/r/proxy_cache_path.

-- 
Maxim Dounin
http://nginx.org/