md-RAID5/6 stripe_cache_size default value vs performance vs memory footprint

[Stan Hoeppner]

On 12/21/2013 5:18 AM, Stan Hoeppner wrote:
...
> For example, I assisted a user with 5x Intel SSDs back in January and
> his system required 4096, or 80MB of RAM for stripe cache, to reach
> maximum write throughput of the devices.  This yielded 600MB/s or 60%
> greater throughput than 2048, or 40MB RAM for cache.  In his case 60MB
> more RAM than the default was well worth the increase as the machine was
> an iSCSI target server with 8GB RAM.

Correction here.  I said above that 80MB was 60MB greater than the
default for his 5 drives.  This should have said 75MB greater than the
default which is 1MB per member device, or 5MB for 5 drives.

-- 
Stan