Hi Justin, I'm not a RAID or kernel developer, but .. do you have enough RAM to support a 32mb stripe_cache_size?! Here on my 7*250Gb SW RAID5 array, decreasing a stripe_cache_size of 8192 to 4096 frees up no less than 120mb of RAM. Using that as a calculation tool, a 32mb stripe_cache_size would require approximately 960mb of RAM! My RAID box only has 1Gb of RAM, so I'm not game to test such a thing. Others on these lists would definitely have a good idea on what's happening :-)
Cheers, Jason On Fri, 2007-02-23 at 06:41 -0500, Justin Piszcz wrote: > Each of these are averaged over three runs with 6 SATA disks in a SW RAID > 5 configuration: > > (dd if=/dev/zero of=file_1 bs=1M count=2000) > > 128k_stripe: 69.2MB/s > 256k_stripe: 105.3MB/s > 512k_stripe: 142.0MB/s > 1024k_stripe: 144.6MB/s > 2048k_stripe: 208.3MB/s > 4096k_stripe: 223.6MB/s > 8192k_stripe: 226.0MB/s > 16384k_stripe: 215.0MB/s > > When I tried a 32768k stripe, this happened: > p34:~# echo 32768 > /sys/block/md4/md/stripe_cache_size > Connection to p34 closed > > I was able to Alt-SysRQ+b but I could not access the console/X/etc, it > appeared to be frozen. > > FYI. > > Justin. > > - > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to [EMAIL PROTECTED] > More majordomo info at http://vger.kernel.org/majordomo-info.html - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
