NAS suddenly became slow in writing new files

[sh4d0wt3ch]

Hi,

I have a QNAP TS-412A with 4 2TB Seagate drives installed configure as RAID 5. The system has been working fine for almost a few months now, read and write access is fast at average of 40-60 MB/s for read and 20-35 MB/s for write. The system is on a gigabit network and a media server is using the QNAP as a source of media files.

After today I have been experiencing slowdowns on the NAS pertaining to write speed, file read is still at a speedy 60MB/s but as soon as I started writing to it via Windows File Explorer it started crawling the read speed will drop and it will take a long time calculating the speed of write transfer until after 20-30 second it will start copying as around 800KB/s to a maximum throughput of 3MB/s. Tried uploading a file via FTP and I still get the same speed.

I tried writing to the NAS with another computer but still get the same slow speed, tried copying the same file to another computer on the network and I get full speed so I assume that the network is working a the same full speed.

This started happening when I updated to the firmware to 3.4.4 Build0718 yesterday, I updated it again today to 3.5.0 Build0816 but still I have the same problem.

I downgraded my firmware back to the original firmware but it still did not resolve the problem.

Need help in resolving the issue.

[scalvin]

The same thing happened here with a TS-859Pro with 8x 2TB (Hitachi) in a RAID5 setup used for incremental rsync backups of several Linux servers via NFS.
Reading was always at full speed, writing crawled to a halt with bursts of several MB every couple of 20s.
Everything else was completely normal and we failed tracing the onset of this to a specific configuration change or software update.
During debugging we ran a full fsck.ext4 on the array using the latest e2fsutils (in order to do that you need to compile yourself a static 64bit binary of e2fsck 1.41.14 (I will attach it to this post, call e2fsck -pvfDC0 /dev/md0 on unmounted partition, but note that it did not help in this case and took several hours, possibly due to memory swapping) and put a USB stick for additional swap space into the NAS box when your filesystem is around 10 or 12TB, see also http://forum.qnap.com/viewtopic.php?p=216117).
Everything was fine, no errors could be found. But nfs write speed was still creepingly slow.

Eventually we gave up on debugging and scrapped the whole setup (which had been working fine for over a year). We started over from factory defaults and configured the whole system for RAID6.
This whole thing is unfortunate and cost us a lot of time for moving around ~9TB of data.
A strange feeling remains because we never got to the bottom of the problem. Things are back to working order now though.

[AlexKe]

Hi sh4d0wt3ch, scalvin

We are tracking on the performance slow down issue. When we find the solution, we will update with you. Thanks for your report.

[guyfoetz]

Hello,

I'm experiencing the same problem on a TS-412. I use it for bacup of my 859. I copied nearly 4.5tb of data (only music and video files) and it became very slow (300-800kb /s) in writing, or it stop compleatly. Reading is not a problem. Faulty server? NO, I experienced the same problem already twice, with 2 different TS-410 using differen HDD, but all from Seagate. Everytime it happened after a lot of files had been copied.

What can it be? corrupt files?

Please help me, I'm getting crazy

Guy

[abricko]

Still same problems with the latest firmware on both of my NAS

[sh4d0wt3ch]

@abricko

We have an active discussion in this thread about this.

http://forum.qnap.com/viewtopic.php?f=189&t=46855

[abricko]

Thanks for the link, did QNAP eer officially respond to the issue?

[sh4d0wt3ch]

Just recently they are trying to connect to users box to research the problem.

[GarfieldPB]

i have a new TS212Turbo with 2*3 GB single drive and the same problem. in the multimedia folder, there are approx. 34000 folder with a large number of mp3 files and the nas stops every MB which is written. But Reading is fast. When a create a new folder on this drive 1, he is also very slow, so it seems that the ammount of files on the HD is the problem.
also the PC always tell me, that the network share name will be invalid, but when i retry, it appears to be there.

[AGS]

Has anyone come up with a simple solution for this. I have a 219P+ with 2 Samsung 2tb drives running on home network with pcs running W7. The writing speed to the NAS from the W7 machine is unbelievably slow - if I start a copy of a 4gb file it runs at 50-150k/s (this is going from my local Cdrive to the NAS via wired network). The odd thing is if I try the opposite (from the NAS to my local Cdrive) it runs at around 3mb/s (so about 20x faster).

I have not much technical expertise so any simple suggestions would be very much appreciated !
ANDY