hi...
> The speed of your disks makes a difference also. No matter how much
> cache you have you are still going to hit your disks. I would say that
> LVD SCSI is a minimum.
agreed.. we use UW SCSI (though on a RAID 5.. bit of a performance hit, but
worth it for the reliability) and see great throughput...
> At the risk of starting a religious war I found that Postgresql-6.4.?
> on FreeBSD 3.0 would create a table more than twice as fast, wall clock
> time, as the same postgres same table on RedHat 5.2. The bigger the
> table the bigger the difference. The machine, a pc, was sitting on my
> desk so I could see and hear it. FreeBSD appeared to be capable of MANY
> more disk accesses per unit of time than RedHat. Important for table
> creation yes, for table access perhaps. Your mileage may vary. BTW
> other than recompiling the BSD kernel to reflect only the hardware
> installed I made no attempt to optimize either system. BTW II The
> same hardware (machine) was used with both OS's.
one of the reasons for this is that the FreeBSD kernel was
compiled from source and the Linux one wasn't.. redhat's stock kernels are
"jack of all trades, masters of none" and 'optimized' for 386. heh. if you
compile the linux kernel from scratch (which you should always do on any system
you want/need decent performance out of) you will notice a HUGE different...
also, it depends on what type of RedHat installation you did.. e.g. did you
alter what daemons run at startup? there are many things run by default
(for the clueless) that are completely unecessary and on a database system
unwanted...
also of interest is how the disk partitions were set up in each system. *shrug*
that being said, i have noticed that FreeBSD can someimtes be faster than
Linux in certain tasks... (these too were wall clock observations =) but
not even near the 2:1 ratio you imply here...
so, all in all, my plea would be to refrain from making eroneous comparisons
between systems.. the only useful comparisons are tests that are reflective of
the real world.. (e.g. w/windows you CAN'T compile the OS, so that's that...
with linux and bsd you most deffinitely SHOULD compile... ) i understand the
enthusiasm for your OS of choice. however, if you give misleading information
and someone actually tries it out and finds that what you said wasn't exactly
accurate, how does reflect on your OS? answer: not very well.
"the means is the end, not the pathway to the end"
--
Aaron J. Seigo
Sys Admin
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