Hi Ceph Community,

Wondering what experiences good/bad you have with EC pools for iops intensive 
workloads (IE: 4Kish random IO from things like VMWare ESXi). I realize that EC 
pools are a tradeoff between more usable capacity, and having larger 
latency/lower iops, but in my testing the tradeoff for small IO seems to be 
much worse than I had anticipated.

On an all flash 3x replicated pool we’re seeing 45k random read, and 35k random 
write iops testing with fio on a client living on an iSCSI LUN presented to an 
ESXi host. Average latencies for these ops are 4.2ms, and 5.5ms, which is 
respectable at an io depth of 32.

Take this same setup with an EC pool (k=2, m=1, tested with both ISA and 
jerasure, ISA does give better performance for our use case) and we see 30k 
random read, and 16k random write iops. Random reads see 6.5ms average, while 
random writes suffer with 12ms average.

Are others using EC pools seeing similar hits to random writes with small IOs? 
Any way to improve this?

Thanks,
Anthony
_______________________________________________
ceph-users mailing list -- ceph-users@ceph.io
To unsubscribe send an email to ceph-users-le...@ceph.io

Reply via email to