[ZODB-Dev] ZEO overhead?

[John Barratt]

I have just started testing ZEO on and have found a similar slowdown of 
3-4x when first loading the objects in the the client cache relative to 
using FileStorage.  I tested using ab with three different pages, with 
varying numbers of objects accessed, running on Zope 2.6.2b5 and tried 
with both ZODB 3.1.2 and 3.2b2 (3.2b2 was generally a little bit quicker 
than 3.1.2).  All with a single ZEO client, running on a dual CPU box.

Shane Hathaway wrote:
> In reality, I think there's little reason why ZEO over a local 
> connection should be noticeably slower than using FileStorage directly. 
>  Network communication time should be dwarfed by hard drive seek time.

Do you mean that ZEO as it is shouldn't be this slow when loading into 
the client cache, or just that it should be able to be coded to be 
almost as fast as FileStorage (eg. using non async code as discussed) 
and it is hence a known issue?

Thanks,

JB.