Forum: NGINX Perceived poor performance

I don't know if this actually IS poor performance - it just feels like 
it.

I'm running nginx and php-fpm on a VirtualBox virtual server.  No other
services are running (other than the standard Ubuntu Precise minor items
for a server).  The VM has four cores and 1G allocated.

Any time I connect to my server it seems to take 3 seconds before the
request is processed.  I've seen some references via Google that
indicate this is TCP related - but I don't know where to look to find
the break.

The second item - which is probably meaningless until the 3 second delay
is resolved - is stress tests from an external server (I'm trying
http://loader.io) start dropping connections after about 30 simultaneous
connections.  From what little I've gathered about nginx performance
this is absurd.
--
Daniel

On 1/12/2013 9:52 PM, Daniel L. Miller wrote:
> the break.
Further tests show me it isn't for all requests - only requests to my
Wordpress sites, which have a much more complex nginx configuration that
other sites which give me instantaneous response.  What (improper)
commands would have such a major slowdown effect?
--
Daniel

On 13/01/13 19:17, Daniel L. Miller wrote:
>> indicate this is TCP related - but I don't know where to look to find
>> the break.
> Further tests show me it isn't for all requests - only requests to my
> Wordpress sites, which have a much more complex nginx configuration
> that other sites which give me instantaneous response.  What
> (improper) commands would have such a major slowdown effect?
a wp config isn't particularly complex.

What database tuning have you done (are the fast ones also using a
database)? yes I know it's remote, but...
What memory are you allocating to the server?
How busy is the physical server?
Are you running a local DNS server?

Sorry I'm not versed in VB, but I run plenty of WP sites off KVM 
servers.

On 1/12/2013 10:28 PM, Steve Holdoway wrote:
>>> the request is processed.  I've seen some references via Google that
> What memory are you allocating to the server?
> How busy is the physical server?
> Are you running a local DNS server?
>
> Sorry I'm not versed in VB, but I run plenty of WP sites off KVM servers.
>
The fast ones are using the same Mysql database.  I've done a little bit
of Mysql tweaking - I periodically run mysqltuner - but I truly don't
think that's the issue.

I've got 1G of RAM allocated to the VM.  The physical server has 16G.

The physical server is a 6-core Opteron.  Under "load" - neither the
host nor the guest show much usage.

I am running a local DNS server (PowerDNS).

While I've already admitted my overall ignorance - I truly don't think
it's anything else.  I've probably munged my nginx wordpress config - I
just don't know HOW!  Getting wordpress multi-site running was quite a
frustration.  I may try to rebuild my config.

One of my issues is I may have tried to be too "elegant" - I like using
multiple include files to try to avoid duplication.  That way multiple
configs can share common setups.  I may have broken the config by
breaking things up too far!  And I don't know if combining fast-cgi
caching with W3 Total Cache is helping or hurting (assuming of course
I'm doing it correctly).

For me, the whole "rewrite" process, particularly the combination of
Wordpress' logic and nginx syntax, has me quite confused.
--
Daniel

On 01/13/2013 07:17 AM, Daniel L. Miller wrote:
[snip]
> Further tests show me it isn't for all requests - only requests to my
> Wordpress sites, which have a much more complex nginx configuration that
> other sites which give me instantaneous response.  What (improper)
> commands would have such a major slowdown effect?

For my Wordpress site I installed nginx-helper in Wordpress:
http://wordpress.org/extend/plugins/nginx-helper/

And added the cache config inspired by these 2 pages:
http://rtcamp.com/tutorials/nginx-wordpress-fastcg...
http://codex.wordpress.org/Nginx

And the Wordpress site became much faster. You do need to build nginx
with the ngx_cache_purge module from:
https://github.com/FRiCKLE/ngx_cache_purge

Wordpress multi-site info here:
http://rtcamp.com/tutorials/wordpress-multisite-su...
http://rtcamp.com/tutorials/nginx-wordpress-multis...

Check the source of the generated pages. It shows some info how long it
took to generate the page.

You may also want to look at your DB and optimize where possible.

Regards,
Patrick