Re: RHEL 4 improvement in use of swap? (compared to RHEL 3)

[Brian Long <brilong cisco com>]

> this server has the settings "1 15 100" there, it is running kernel 
> 2.4.21-20.ELsmp and has uptime 183 days. I am sure that the kernel is 
> exactly the one which showed that bad behaviour I described and caused 
> many outages to our service. I am not sure about the settings in 
> /proc/sys/vm/pagecache, but I think that they were not changed from 
> their default. One correction to my original message: this server has 4 
> GB RAM, not 2 GB RAM. Right now I cannot experiment with this server, 
> because it runs fine and I couldn't justify any outages for the very 
> important services running there. If we would do anything there, we 
> would install RHEL 4 on another server and switch our services there. I 
> am sorry, but this is a 24x7 production environment and we have no room 
> for experiments...

Why would you have a critical machine in place and not be able to
reproduce the error on a development or test  server?  I'm used to a
different model.  Everything is developed in dev, tested in stage and
then put into production.  Yes, it means 3 servers for each production
service, but it's worth it.

FYI, I was wrong about pagecache.  The old values were 1 15 100 and the
new values are 1 15 30.  This means pagecache will only occupy 30% of
your total RAM.

/Brian/

-- 
       Brian Long                      |         |           |
       IT Data Center Systems          |       .|||.       .|||.
       Cisco Linux Developer           |   ..:|||||||:...:|||||||:..
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