Skip to content
View in the app

A better way to browse. Learn more.

Unraid

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

Slow write speed to cache drive (40MB/s)

Featured Replies

Hi,

I have slow write speeds to cache disk (around 40MB/s)


Scenario:
Docker hosting Sonarr/Radarr copying files from M.2 disk on a PC to separate Unraid server

Copying to Unraid SSD in share (https://www.amazon.co.uk/gp/product/B09XDJ673F

Mostly 10gbps capable network but capped by 2.5gbps NIC on the Sonarr PC. 
Network tested with iperf confirming 2gbps+ speeds between machines

Unraid SSD tested with DiskSpeed - showing 200MB/s 
M.2 tested with Ubuntu benchmark - showing 3000MB/s+

The SSD had previously been filled so I trimmed and this appeared to help (network was showing ~2.5gbps inbound traffic immediately after trim) but it quickly degraded again. Subsequent trims haven't really helped

 

Has anyone experienced similar? Appreciate any suggestions!

beamish-nas-diagnostics-20220926-1537.zip

Solved by JorgeB

  • Community Expert

Enable turbo write and copy directly to the array, that will help test if it's a cache device problem.

  • Author

Writing directly to the array it is fluctuating 100-200MB/s, maxing out 2.5gbps inbound traffic

 

  • Community Expert
  • Solution

That suggest the SSD you are using is just slower, suggest getting one known to perform better, like the Samsung 870 EVO or Crucial MX500 for example.

  • Author

Thank you

 

May as well get an M.2 ready for the 10gbps network in that case

 

Is it fine to use an M.2 with a PCI-E adapter?
 

Are there any recommended M.2 models for Unraid?

  • Author

Never mind, I've ran out of PCI slots 

Ordered a Crucial MX500 as advised

Will report back once that's confirmed to fix the issue 

  • 2 weeks later...
  • Author

Just to confirm, the Crucial SSD is working as expected

Significantly faster write speeds from the second machine to the NAS with cache mode activated

 

Thanks again @JorgeB, I really appreciate your help!

Just found a post from @tbonedude420 which may explain my issue. If this is the case would the introduction of a further "faster" drive, as part of the array be possible? That way downloads are made direct to NVME, but then when copying to the array for permanent storage (and currently bringing the system to a halt, potentially because my mechanical array HDD's can't keep up) I could have them copied to a faster SSD or something similar as a kind of bridge. I don't know if this is even possible, but at this point I'm open to any solution to remedy this issue.

 

Screenshot_20221008_204735_Firefox.thumb.jpg.95dc30a8d9f745c6f65661b8a41f79eb.jpg

Edited by BeardedNoir

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.