RAID10 without write-back cache = horrible write performance?
- by Harry Mexican
I have just provisioned a dedicated server on singlehop.
I'm running it through some tests to know what to expect performance-wise. On the I/O side (with 4 1TB disks in RAID 10) I get:
write-cache disabled
200 MB/s read throughput
30 MB/s write throughput
I thought that was really low compared to my desktop HD which gets 150-150 or so.
So I had a chat with them and they suggested enabling the write cache. New results:
write-cache enabled
280 MB/s read
260 MB/s write
which is great and all but means I'd have to add a BBU for an additional monthly cost.
Is it normal for the write throughput to be 1/4 of a regular drive on RAID10, if you don't have write cache? It almost feels like its intentionally bad to force you to pony up for the BBU. I'd be happy with normal non-raid performance of 150/150.