Peaks And Valleys

[KMR]

Hello again everyone. I have been busy with work lately and haven't been doing much tinkering with my NAS (just been using it to serve up media) but this weekend I installed the SABnzbd plugin after getting poor speeds with the VM that used to host it. I have added 4 1TB drives in two mirrored vdevs; one of the vdevs hosts the plugin and downloads folder that I use before I transfer things over to the main raidZ2 vdev. I plan to use the second mirror to host VMs in the future.

I have a 175mbps internet connection and I get fairly steady 150mbps speeds which I am happy with. The issue is that every few minutes (downloading at 15MB/s or so) everything drops to zero. The reporting tool in the FreeNAS GUI shows cpu and network traffic dropping to zero for a few seconds and then picking up to full speed again. I see the hits on my router traffic graphs as well (pfSense). The CPU utilization never gets above 75 of 200. I assume 200 is the actual max for the dual core proc I have currently in the machine, am I wrong here? If that assumption is correct it isn't getting CPU bound. Memory utilization shows about 4GB free (16GB total). When I run iostat -xd 5 it shows what I think are reasonable service times and the queue depth never gets over 10. Then when the drop happens all activity on the disks drops to zero.

Sample iostat output:

device r/s w/s kr/s kw/s qlen svc_t %b
md0 0.0 0.0 0.0 0.0 0 0.0 0
md1 0.0 0.0 0.0 0.0 0 0.0 0
md2 0.0 1.2 0.0 0.0 0 0.0 0
md3 0.0 0.0 0.0 0.0 0 0.0 0
ada0 0.2 321.3 1.6 32973.4 10 6.2 20
ada1 3.4 290.9 14.4 30347.5 10 9.1 29
ada2 0.0 0.0 0.0 0.0 0 0.0 0
ada3 0.0 0.0 0.0 0.0 0 0.0 0
ada4 0.0 0.0 0.0 0.0 0 0.0 0
ada5 0.0 0.0 0.0 0.0 0 0.0 0
da0 0.0 0.0 0.0 0.0 0 0.0 0
da1 0.0 0.0 0.0 0.0 0 0.0 0
da2 0.0 0.0 0.0 0.0 0 0.0 0
da3 0.0 0.0 0.0 0.0 0 0.0 0
da4 0.0 0.0 0.0 0.0 0 0.0 0
pass0 0.0 0.0 0.0 0.0 0 0.0 0
pass1 0.0 0.0 0.0 0.0 0 0.0 0
pass2 0.0 0.0 0.0 0.0 0 0.0 0
pass3 0.0 0.0 0.0 0.0 0 0.0 0
pass4 0.0 0.0 0.0 0.0 0 0.0 0
pass5 0.0 0.0 0.0 0.0 0 0.0 0
pass6 0.0 0.0 0.0 0.0 0 0.0 0
pass7 0.0 0.0 0.0 0.0 0 0.0 0
pass8 0.0 0.0 0.0 0.0 0 0.0 0
pass9 0.0 0.0 0.0 0.0 0 0.0 0
pass10 0.0 0.0 0.0 0.0 0 0.0 0

Any thoughts here?

 

[KMR]

Really? Nothing?

I installed the SABnzbd plugin on the FreeNAS box and I get basically the full 175Mbps down but an still experiencing the intermittent drops to nothing then back up to full speed. Does anyone know of any tests that I can run? Scrubs reveal no issues.

 

[cyberjock]

Not off the top of my head. My first guess is that there is a network issue somewhere. Maybe dropped packets or bad cabling leading to issues that cause the NIC　ｔｏ　ｓｔｏｐ　ｔｒａｎｓｍｉｔｔｉｎｇ　ａｎｄ　ｗａｉｔ　ｆｏｒ　ａ　ｒｅｓｐｏｎｓｅ．

Ｓｏｒｒｙ　ａｂｏｕｔ　ｔｈｅ　ｆｏｎｔｓ．　　Ｔｈｅｙ　ｒａｎｄｏｍｌｙ　ｃｈａｎｇｅ　ｎｏｗ　ａｎｄ　ｄｅｓｐｉｔｅ　ｂｅｉｎｇ　ａ　ｍｏｄｅｒａｔｏｒ　Ｉ can't fix them....