Low data rate

[OFFREAL]

Hello!

I'm use FreeNAS 9.2.1.7 x32

Gigabit Ethernet D-link DGE-528T
Intel Pentium IV 3.0 GHz
RAM 1024 GB ( 2 x 512 )
Data HDD: ST31000340AS ( 1.0 TB ) SATA
System HDD: WD400JB (40 GB) IDE

When I start to download a large file (about few gigabytes), the speed reaches 40-60 MB s, but a few minutes later drops sharply to almost zero (about 50-100 kB/s). And does not return to previous values until the system reboots.

I have this problem on FTP and CIFS (SMB)..

1000 MB LED indicator on ethernet card is flashing
CPU Load < 5%
Free RAM > 300 MB
SWAP Utilization: 0.0
SMART on HDDs is good (check in Victoria)

Of course, I tried to configure built in motherboard 100 MB network card, but still have this problem.

What's the problem?

 

[DrKK]

The problem is that you are using 1GB of RAM. Performance and stability of FreeNAS 9.2.1.7 will be very poor with 1GB of RAM. Probably, what happens is your (unbelievably small) ARC fills up, and you don't get your MRU and MFU caches working for you, but rather, against you, once they're filled.

Then when you reboot, all the caches start anew, and it's fine.

Until they fill again.

Your hardware is not good enough for modern FreeNAS.

 

[OFFREAL]

Thank you!

Strange reason, because, shortly before that, I tried to upload 500GB of data to the FreeNAS share via 100Mbps interface and it worked fine! (11-11.5 MBps and about 15 hours)

This is running processes window when data transfer is active:
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
last pid: 6062; load averages: 0.03, 0.03, 0.00 up 0+01:14:48 16:59:53
27 processes: 1 running, 26 sleeping

Mem: 99M Active, 89M Inact, 339M Wired, 25M Buf, 394M Free
ARC: 218M Total, 2806K MFU, 214M MRU, 144K Anon, 388K Header, 1005K Other
Swap: 2048M Total, 2048M Free
...
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

If the system has free memory, why is it not used?

 

[DrKK]

The way ZFS is done, a certain amount of memory is kept free for various reasons. You can't use all the memory.

In most cases, you want nearly 1GB free. :)

 

[cyberjock]

218MB for ZFS.. that's HILARIOUS!!!!!!

 

[OFFREAL]

Thanks, I understand.

If I will use UFS, whether this will require fewer resources?
How do I mount the ZFS-drive on windows 7 to save my data? Or are there other ways?

218MB for ZFS.. that's HILARIOUS!!!!!!

This is my old hardware :)
How much memory is optimal for ZFS?

 

[cyberjock]

Optimal = infinite RAM. (Seriously).

The reality is you need 8GB of RAM to use FreeNAS safely. Go with less and you run the risk of a crash making your pool unmountable forever. You know, just like the manual says.

 

[OFFREAL]

I'm use VMware Player on Windows 7 for install FreeNAS and mount ZFS-hdd :) It work fine on 4GB RAM ...
Thank you all!

Hmmm...
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
last pid: 5402; load averages: 1.11, 0.73, 0.62 up 0+00:42:53 19:12:21
31 processes: 2 running, 29 sleeping

Mem: 96M Active, 70M Inact, 339M Wired, 1164K Cache, 28M Buf, 2490M Free
ARC: 208M Total, 4991K MFU, 201M MRU, 144K Anon, 561K Header, 1178K Other
Swap: 2048M Total, 2048M Free
...
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

208M and work fine.

 

[DrKK]

wow. This keeps getting better :)