Why are NFS writes half of SMB and Afp?

[Gessi]

Hello,

I am a bit confused as i get half of write throughput for same dataset shared via NFS than for Smb or Afp?

My MacBookPro gives me 105MB/s write and 110MB/s read for Afp and Smb but only 55MB/s write for NFS and 105 MB/s read for NFS?

I am confused as i share same dataset to same MacBook via same network link but NFS writes are so much slower?

Can someone just give me some direction?

I prefer sharing via NFS because I share same dataset to multiple computers as Linux, Kodi etc.

 

[depasseg]

NFS uses Sync writes.

 

[Gessi]

NFS uses Sync writes.

Seems that my single threaded test does not fit NFS then...hmmm... Nees to make a realistic use case test obviously

 

[depasseg]

Try disabling sync in NFS and see if performance improves. Also run zilstat during a transfer to see what's going on.

If sync is the issue, you need a SLOG device to speed it up.

 

[Gessi]

Try disabling sync in NFS and see if performance improves. Also run zilstat during a transfer to see what's going on.

If sync is the issue, you need a SLOG device to speed it up.

Is sync disabled by a tunable on FreeNAS?

SLog tells me nothing just ZIL for writes but i have 2 spare SSD which i could use for either or both use cases as i havent identified usage for the SSDs yet.

 

[depasseg]

Is sync disabled by a tunable on FreeNAS?

No, it would be part of the NFS client config.

As long as the SSD's have their own power protection, they are suitable. Depending on your usage, you need to look at the write profile and ensure your device has the proper endurance.

 

[Gessi]

No, it would be part of the NFS client config.

As long as the SSD's have their own power protection, they are suitable. Depending on your usage, you need to look at the write profile and ensure your device has the proper endurance.

Thanks buddy! I was using standard Apple OS X finder behaviour running on Yosemite which obviously does not mount NFS Exports with sync disabled and I would like to stay with default setting and usage if somehow possible when rolling out FreeNAS to other users with MacOS.

Anyway I attached 2xSSD (Samsung Evo 850) and added thoses as mirrored ZIL and the rest of the disks as L2ARC and the NFS write performance increased to ~78MB/s which is 50%+...

I am using the Application "Black Magic Disk Speed Test" on my Mac with a 1GbE NIC connected to my FreeNAS with 2x1GbE on LACP... I know those performance tests do mostly not mirror a real environment as 80%+ of filesystem access would be reads so I am quite happy with the current numbers as it maxes out my NIC while reading and gets a lot from write as well.

 

[depasseg]

mirrored ZIL

Technically, this is a mirrored SLOG (The ZIL is always there, but without a SLOG, the ZIL is on the Pool. So if the pool is slow, so are the sync writes).

Running the zilstat command should give you some insight into the ZIL.