raidz2 a bit big

[Randy Bush]

>>    NAME    STATE   READ WRITE CKSUM
>>    tank    ONLINE    0   0   0
>>     raidz2  ONLINE    0   0   0
>>      da0s3  ONLINE    0   0   0
>>      da1s3  ONLINE    0   0   0
>>      da2s1  ONLINE    0   0   0
>>      da3s1  ONLINE    0   0   0
>>      da4s1  ONLINE    0   0   0
>>      da5s1  ONLINE    0   0   0
>>      da6s1  ONLINE    0   0   0
>>      da7s1  ONLINE    0   0   0
>>      da8s1  ONLINE    0   0   0
>>      da9s1  ONLINE    0   0   0
>>      da10s1 ONLINE    0   0   0
>>      da11s1 ONLINE    0   0   0
> 
> Reads on such configurations are very slow.

how are writes?

> If one of your disk, for example, is capable of 100 IO per/sec, then:
> with 12 disks in one raidz2 vdev you get only 100 IOPS
> with 4 disks in raidz2 (total 3 raidz2 vdevs) you get 300 IOPS
> with 2 disks in mirror (total 6 mirror vdevs) you can get 1200 IOPS

ok.  sounds nice.  but then, don't i have six file systems and have to
start playing lay-out design games?

randy