[Koha] Very small library, low-end hardware

[Christopher Hicks]

On Thu, 4 Sep 2003, Chris Cormack wrote:

> Yep, I think to get some real speed increases, we'd need to look into
> mod_perl and Apache::DBI to get some connection pooling.

I plan on doing this after 2.0 comes out if noone else beats me to it.

CGI is great for development, but crapola for serious deployment.  :)  
mod_perl rocks and they've got the 'beta' mod_perl for apache 2.0 
thoroughly bug fixed at this point.  2.0 offers whole new avenues for 
tweaking things to improve performance.  "Maybe a multi-threaded apache 
would make intel hyperthreading useful under linux, let's try...."

> I suspect that starting up perl, and making database connections are 2 of
> the bottlenecks.

Oh yes.  Even MySQL takes a significant time to setup a database
connection compared to the rest of the perl script.  Sadly that's nothing
compared to the heavyweight time required to connect to heavyweight
database like Oracle and DB2.

I actually had a really scary script come across my desk a year ago,
written by a very smart scientist (sigh).  The script had a database
connection to a server three states away inside the inner loop that ran 50
times for every script invocation.  Apparently they needed a consultant to
explain to them that the script as written was going to take 45 secs per
CGI invocation, that it couldn't run in mod_perl because the Perl was so
very ugly, and oh by the way, pull this out of the inner loop and things
will get much quicker.  Despite that, in looking at profiling data
throughout that process to see where the script was really sucking wind
the SQL connection portion of things and loading modules were the real
crunchers.

Loading DBI and doing a database connection on a P90 isn't too painful.  
On older hardware the slow I/O tends to make Perl seem slower because it
pulls in so many different files and processes them when it starts up.  
That still doesn't mean the old hardware is useless for Perl/Koha, but 
that a different strategy might be required - like a Perl daemon 
accepting telnets.

> But once we get 2.0 out, we can do some work with the profiler tools and
> spot any bottlenecks and fix them.

Profiling is pretty easy to do and and can be extremely helpful.  It may
or may not surprise you with its answers, but it's so nice to see and have
real numbers.

-- 
</chris>

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