[Koha] [Koha-devel] Performance of Koha and usage of remote MySQL server

[Dobrica Pavlinusic]

On Thu, Apr 05, 2012 at 02:03:02PM +0200, jonathan DUPERRIER wrote:
> Hello,
> 
> I would like to know if the installation of Koha with a MySQL
> database on another server than the application may affect the
> performance of Koha. The MySQL server and application are on the
> same LAN, regardless of any order might be slowdown during query
> execution.

It seems it does.

I did some measurements with DBD::Gofer which is network serialisation
layer which can introduce local cache with:

DBI_AUTOPROXY=dbi:Gofer:transport=null;cache=1

This pass SQL query to original database, but cache queries in memory,
just like MySQL query cache does.

This has performance impact on generated search page:

2.952961 s page load time and 0.713 s of DBI time to
3.709371 s page load time and 1.634 s of DBI time

This are plack numbers, but are useful for estimating performance
implact of Gofer itself. It roughly doubles number of perl statements
execuited in NYTProf.

And now numbers from caching layer: we issue 1674 queries of which 927 are
unique. That means we are generating double traffic to database so using
local caching via DBD::Gofer (which is part of standard DBI install,
BTW) might buy you some performance.

There are some low-hanging fruit to pick here, I think :-)


-- 
Dobrica Pavlinusic               2share!2flame            dpavlin at rot13.org
Unix addict. Internet consultant.             http://www.rot13.org/~dpavlin