Re: possible improvement between G4 and G5

>>>>> "JB" == Josh Berkus <josh(at)agliodbs(dot)com> writes:

JB> Aaron,
>> I do consulting, so they're all over the place and tend to be complex. Very
>> few fit in RAM, but still are very buffered. These are almost all backed
>> with very high end I/O subsystems, with dozens of spindles with battery
>> backed up writethrough cache and gigs of buffers, which may be why I worry
>> so much about CPU. I have had this issue with multiple servers.

JB> Aha, I think this is the difference. I never seem to be able to
JB> get my clients to fork out for adequate disk support. They are
JB> always running off single or double SCSI RAID in the host server;
JB> not the sort of setup you have.

Even when I upgraded my system to a 14-spindle RAID5 with 128M cache
and 4GB RAM on a dual Xeon system, I still wind up being I/O bound
quite often.

I think it depends on what your "working set" turns out to be. My
workload really spans a lot more of the DB than I can end up caching.

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