At what rate does your disk setup write sequential data, e.g.:
time dd if=/dev/zero of=bigfile bs=8k count=500000
(sized for 2x RAM on a system with 2GB)
BTW - the Compaq smartarray controllers are pretty broken on Linux from a
performance standpoint in our experience. We've had disastrously bad
results from the SmartArray 5i and 6 controllers on kernels from 2.4 ->
2.6.10, on the order of 20MB/s.
For comparison, the results on our dual opteron with a single LSI SCSI
controller with software RAID0 on a 2.6.10 kernel:
[EMAIL PROTECTED] dbfast]$ time dd if=/dev/zero of=bigfile bs=8k
500000+0 records in
500000+0 records out
Which calculates out to about 161MB/s.
On 7/21/05 2:55 PM, "Mark Wong" <[EMAIL PROTECTED]> wrote:
> I just ran through a few tests with the v14 patch against 100GB of data
> from dbt3 and found a 30% improvement; 3.6 hours vs 5.3 hours. Just to
> give a few details, I only loaded data and started a COPY in parallel
> for each the data files:
> Here's a visual of my disk layout, for those familiar with the database
> I have 6 arrays of fourteen 15k rpm drives in a split-bus configuration
> attached to a 4-way itanium2 via 6 compaq smartarray pci-x controllers.
> Let me know if you have any questions.
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