I have a RAIDZ2 pool. When running a read test (dd, not cached) I get about 110MB/s on 5400rpm consumer SATA3 drives.
I looked at the disk reporting page (busy and latency) during the test and found the following:
da0, da2, da3:
Busy 40%, Read latency: 1-2ms, no write or delete
da1:
Busy 100%, Read latency: 6-7ms, delete: 10-40ms, no write.
Under almost no load the delete latency for all drives is 0, except da1 which hovers at around 1-2ms.
What is a "delete" operation? da1 is a new WD20EZAZ with 1560 power on hours and no errors on a long self test. I have much older drives that I would expect to be slower than this one. I don't keep new or expensive drives in my pool.
Thanks.
I looked at the disk reporting page (busy and latency) during the test and found the following:
da0, da2, da3:
Busy 40%, Read latency: 1-2ms, no write or delete
da1:
Busy 100%, Read latency: 6-7ms, delete: 10-40ms, no write.
Under almost no load the delete latency for all drives is 0, except da1 which hovers at around 1-2ms.
What is a "delete" operation? da1 is a new WD20EZAZ with 1560 power on hours and no errors on a long self test. I have much older drives that I would expect to be slower than this one. I don't keep new or expensive drives in my pool.
Thanks.