[ZODB-Dev] write performance

Nicholas Henke henken@seas.upenn.edu
Wed, 5 Feb 2003 16:30:42 -0500


On Wed, 5 Feb 2003 14:03:02 -0500
Greg Ward <gward@mems-exchange.org> wrote:

> On 03 February 2003, Nicholas Henke said:
> > 3) Are unix domain sockets really faster than normal sockets when
> > connections are limited to the localhost ?
> 
> My understanding -- based purely on hearsay and folklore -- is that in
> modern Unices, inet-domain sockets to 127.0.0.1 are just as fast as
> Unix-domain sockets.  I've never bothered with benchmarking it though
> -- if you're really concerned about it, you should do some timing
> tests!

OK -- that is what I thought, but I figured I would ask anyways.

> 
> Also, keep in mind that ZODB is designed for frequent reads and
> infrequent writes.  You might be hitting fundamental design issues, or
> you might just be hitting inefficient code that no one has bothered to
> optimize.  Try profiling: hotshot works pretty well if you can dig up
> Fred's presentation from IPC10 (the only docs AFAIK).
> 
>         Greg
> 

I have pretty extensive hotshot data -- where shall I dump it ? It does
look as if ZODB/ZEO is taking a bit of time...

Nic

-- 
Nicholas Henke
Linux Cluster Systems Programmer
Liniac Project - Univ. of Pennsylvania