SSD cache random writes extremely slow

Questions about SNMP, Power, System, Logs, disk, & RAID.
Post Reply
iscoffeelife
New here
Posts: 3
Joined: Mon Apr 26, 2021 4:13 pm

SSD cache random writes extremely slow

Post by iscoffeelife »

Upgraded our TS 1231XU/RP by adding 2 Ironwolf 500GB SATA NAS SSDs as SSD cache (rated for 550MB/s read/write) for improved random I/O-write performance (and potentially improved read speed).

Mostly we will be network limited - but currently I get random write speeds of 200KB/s - 1MB/s - before the upgrade and the same speed after adding the SSD cache.

SSDs are configured in RAID 1 with 30% overprovisioning and 1MB block size - limiting to random I/O or all I/O does not seem to make a difference.


As we are only connected to a 1Gb/s connection I'm not expecting much; 40-50MB/s would already be a great improvement.

When doing serial read / writes I achieve 40-50MB/s - so the network will carry this amount of data.


Is there something I'm missing here - it looks like it's completely bypassing the cache? I followed the SSD cache configuration guide and am running the most recent software.

Other drives are 4x IronWolfs 7200 RPM 8TB - Raid 5 static volume.
iscoffeelife
New here
Posts: 3
Joined: Mon Apr 26, 2021 4:13 pm

Re: SSD cache random writes extremely slow

Post by iscoffeelife »

Firmware: 4.5.2.1630 build 20210406
Client OS: Windows 10
iscoffeelife
New here
Posts: 3
Joined: Mon Apr 26, 2021 4:13 pm

Re: SSD cache random writes extremely slow

Post by iscoffeelife »

After running this setup for ~2 weeks the performance issues are still the same. I guess I should contact QNAP support.
User avatar
dolbyman
Guru
Posts: 35030
Joined: Sat Feb 12, 2011 2:11 am
Location: Vancouver BC , Canada

Re: SSD cache random writes extremely slow

Post by dolbyman »

correct...dont think many people here run a 12 disk arm machine
Post Reply

Return to “System & Disk Volume Management”