Remove array drive to mount as read only on a Linux system then return it?

[dev_guy]

This is a bit odd but I wanted to see if I'm going to break anything (namely parity) if I try this? Can I shutdown my server, remove a XFS data drive from the array, mount it read only on a Linux system to work with the data on the drive, and then return it to the array? If it's mounted as read only while out of the array will everything be okay? Or am I missing something?

 

The reason for doing this is strictly performance. It's 12TB of data, with half a million files, and accessing it over the LAN via Unraid is proving to be painfully slow and easily an order of magnitude slower than having it be a local SATA drive. For whatever reason Unraid is rather slow for a large number of small reads over the LAN.

 

So will my array never miss the drive being borrowed for a while as read only? Or will some bit get flipped somewhere throwing off the block parity calculations?

[JorgeB]

11 hours ago, dev_guy said:

If it's mounted as read only while out of the array will everything be okay?

Yes, that's fine.

 

Alternatively and if you haven't yet, you could first try updating to v6.11, SMB performance is much better, and/or enable disk shares and transfer directly from it, it's always faster than using user shares especially with small files.

[dev_guy]

1 hour ago, JorgeB said:

Yes, that's fine.

 

Alternatively and if you haven't yet, you could first try updating to v6.11, SMB performance is much better, and/or enable disk shares and transfer directly from it, it's always faster than using user shares especially with small files.

 

@JorgeB thanks for the answer and suggestions! I wasn't aware SMB is significantly better in 6.11. The disk share idea is also interesting. I believe the file I/O in Unraid shares is perhaps going through Fuse? If so, that would help explain the abysmal performance reading large numbers of small files.

 

I know NFS offers much better performance with small files as well. So perhaps NFS plus a disk share might approach the speed of the drive itself.

[JorgeB]

42 minutes ago, dev_guy said:

I believe the file I/O in Unraid shares is perhaps going through Fuse?

Yes, like mentioned it's much better with v6.11.0 and newer due to s Samba update, but there's always some overhead, and using a disk share is always faster.