[ZODB-Dev] Problems packing Zope 2.9.8 storage

[Shane Hathaway]

Chris Withers wrote:
> Shane Hathaway wrote:
>> Chris Withers wrote:
>>> I thought RelStorage was slow at packing?
>> Not anymore.  I optimized packing last December/January and it has been 
>> plenty fast ever since, AFAIK.
> 
> Interesting. Got any metrics on its speed compared to FileStorage, 
> including packing?

I don't have numbers on pack speed, but I've eliminated all the speed 
issues people have brought up.

People have been looking at these performance charts for quite a while:

http://shane.willowrise.com/archives/how-to-fix-the-mysql-write-speed/
http://shane.willowrise.com/archives/relstorage-111-coming-soon/
http://shane.willowrise.com/archives/relstorage-10-and-measurements/

Look at this chart in particular, which suggests that RelStorage with 
PostgreSQL or MySQL is several times faster than ZEO for heavy read loads:

http://shane.willowrise.com/wp-content/uploads/2009/03/relstorage-113-speed-10k.png

I am waiting for someone to dispute these results.  I *want* ZEO to be 
faster, since its code paths are simpler than any relational database, 
but the performance measurements suggest that under pressure, RelStorage 
with MySQL or PostgreSQL can read 3 objects in the time it takes ZEO 
with FileStorage to read 1.

Shane