[Cbe-oss-dev] ps3vram performance

[Ken Werner]

On Saturday 05 September 2009 06:55:46 pm Kevin Locke wrote:
> On Tue, 2009-09-01 at 01:13 +0300, Siarhei Siamashka wrote:
> > How fast is ps3vram supposed to be? [...]
> >
> > Also 'dd if=/dev/ps3vram of=/dev/null bs=1M' shows throughput something
> > like 29MB/s and this does not look very impressive. Does anybody have
> > better performance?  [...]
> 
> I hadn't thought to measure it until you asked.  Here's another data
> point for you:
> 
> North American 40GB Model (CECHG)
> PS3 firmware version 2.8.0
> 
> # dd if=/dev/ps3vram of=/dev/null bs=1M iflag=direct
> 245+0 records in
> 245+0 records out
> 256901120 bytes (257 MB) copied, 6.52754 s, 39.4 MB/s
> # dd of=/dev/ps3vram if=/dev/zero bs=1M oflag=direct
> dd: writing `/dev/ps3vram': No space left on device
> 246+0 records in
> 245+0 records out
> 256901120 bytes (257 MB) copied, 13.0163 s, 19.7 MB/s

I did some testing on a 40GB Model (CECHG04). Here are the numbers:

# FW 2.7.6, Kernel 2.6.30.5-43.fc11.ppc64 (stock Fedora 11)
# dd if=/dev/zero of=/dev/ps3vram  count=229 bs=1M oflag=direct
229+0 records in
229+0 records out
240123904 bytes (240 MB) copied, 3.88861 s, 61.8 MB/s
# dd if=/dev/ps3vram of=/dev/null bs=1M iflag=direct
236+0 records in
236+0 records out
247463936 bytes (247 MB) copied, 1.96822 s, 126 MB/s

# FW 3.0.1, Kernel 2.6.30.5-43.fc11.ppc64 (stock Fedora 11)
# dd if=/dev/zero of=/dev/ps3vram  count=229 bs=1M oflag=direct
229+0 records in
229+0 records out
240123904 bytes (240 MB) copied, 3.90034 s, 61.6 MB/s
# dd if=/dev/ps3vram of=/dev/null bs=1M iflag=direct
236+0 records in
236+0 records out
247463936 bytes (247 MB) copied, 1.9592 s, 126 MB/s

# FW 3.0.1, Kernel 2.6.31-rc7 (ps3_defconfig)
# dd if=/dev/zero of=/dev/ps3vram  count=229 bs=1M oflag=direct
229+0 records in
229+0 records out
240123904 bytes (240 MB) copied, 14.612 s, 16.4 MB/s
# dd if=/dev/ps3vram of=/dev/null bs=1M iflag=direct
245+0 records in
245+0 records out
256901120 bytes (257 MB) copied, 7.85136 s, 32.7 MB/s

# FW 3.0.1, Kernel 2.6.31 (ps3_defconfig)
# dd if=/dev/zero of=/dev/ps3vram  count=229 bs=1M oflag=direct
229+0 records in
229+0 records out
240123904 bytes (240 MB) copied, 14.5785 s, 16.5 MB/s
# dd if=/dev/ps3vram of=/dev/null bs=1M iflag=direct
245+0 records in
245+0 records out
256901120 bytes (257 MB) copied, 7.85101 s, 32.7 MB/s

It looks like the firmware from 2.7.6 to 3.0.1 update has no impact but the 
kernel version does.

-ken