Bart Van Assche wrote:
On Jan 24, 2008 8:06 AM, Robin Humble <robin.humble+stgt@xxxxxxxxxx> wrote:
On Tue, Jan 22, 2008 at 01:32:08PM +0100, Bart Van Assche wrote:
.............................................................................................
. . STGT read SCST read . STGT read SCST read .
. . performance performance . performance performance .
. . (0.5K, MB/s) (0.5K, MB/s) . (1 MB >MB/s) (1 MB, MB/s) .
.............................................................................................
. Ethernet (1 Gb/s network) . 77 78 . 77 89 .
. IPoIB (8 Gb/s network) . 163 185 . 201 239 .
. iSER (8 Gb/s network) . 250 N/A . 360 N/A .
. SRP (8 Gb/s network) . N/A 421 . N/A 683 .
............................................................................................
how are write speeds with SCST SRP?
for some kernels and tests tgt writes at >2x the read speed.
Robin,
There is a fundamental difference between regular dd-like reads and
writes: reads are sync, i.e. latency sensitive, but writes are async,
i.e. latency insensitive. You should use O_DIRECT dd writes for the fair
comparison.
Vlad
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