New pool with new drives and not faster

[ondjultomte]

I had a old pool with 6x 4TB sata drives with no frills, fio benchmark below

https://imgur.com/a/hUew9

good write performance at around 400MBps old drives from 2016.

I got a new pool with 8x 10TB SAS drives which I get the worse from, its more uneven! in seq write that is.

This is not expected, with drives that can read/write at 200MBps compared to 100 of the old sata drives I expeced to get more seq performance outof this new setup.

I need to ideas how to tweak or understand this behaviour better.



above

 

[ondjultomte]

 

[ondjultomte]

hardware on server is

SM x10srh
Xeon E5 2695v4
128GB ram

the old pool sits in a server with
Intel Xeon Silver 4108 (16) @ 3.000GHz
some dell MB
16GB ram

 

[ondjultomte]

benchmark again with 64G file

new pool

vs old pool

 

[ondjultomte]

are there cpu limitations here?

 

[ondjultomte]

Its silly but look at each drive performing much better with to old sata sompared to the 10TB sas drives!

 

[ondjultomte]

the new this which are on datasheet twice as fast are in reality twice as slow! ...

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[sretalla]

I notice a key difference is you added SLOG and L2ARC (in addition to the special VDEV).

Perhaps remove the SLOG and L2ARC first and retry your tests.

 

[ondjultomte]

are we seeing pci limitation ? or cpu ?

 

[ondjultomte]

I notice a key difference is you added SLOG and L2ARC (in addition to the special VDEV).

Perhaps remove the SLOG and L2ARC first and retry your tests.

I could try that, but that should defenetly only just improve things if eg synced writes.

 

[ondjultomte]

I can do the otherway around! add slog and l2arc to the old pool :)

 

[ondjultomte]

wow, adding the slog and l2arc made the old pool faster ! :)

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600MBps