# Re: \[PATCH 0/1\] RFC: Unreliable discard performance can cripple RAID1

- From: Martin K. Petersen \<hidden\>
- Date: 2015-06-25 01:03:52 
- List: linux-raid
- Page: https://ratatoskr.run/linux-raid/2015/06/6629937
- Thread: https://ratatoskr.run/linux-raid/2015/06/6629937/t.md

```text
>>>>> "Jes" == Jes Sorensen [ref] writes:

Jes> We already disable discard per default on raid456 in a similar
Jes> manner because some of them unreliably reports discard_zeroes_data
Jes> when they in reality don't.

Jes> If there was a way to reliably detect these things it would be
Jes> fine, unfortunately there isn't.

We whitelist drives that do the right thing now.

-- 
Martin K. Petersen	Oracle Linux Engineering
```