Re: [PATCH] add --throttle option to pgbench

> I'm having a hard time understanding the use-case for this feature.

Here is an example functional use case I had in mind.

Let us say I'm teaching a practice session about administrating 
replication. Students have a desktop computer on which they can install 
several instances or postgresql, or possibly use virtual machines. I'd 
like them to setup one server, put it under a continuous load, then create 
a first slave, then a second, and things like that. The thing I do not 
want is the poor desktop and its hard drive to be at maximum speed for the 
whole afternoon while doing the session, making it hard to do anything 
else on the host. So I want something both realistic (the database is 
under a load, the WAL is advancing, let us dump it, base backup it, 
replicate it, monitor it, update it, whatever...), but gentle all the 
same.

Using pgbench with --throttle basically provides the adjustable continuous 
load I need. I understand that this is not at all the intent for which it 
was developed.

Note that I will probably propose another patch to provide a heart beat 
while things are going on, but I thought that one patch at a time was 
enough.

-- 
Fabien.