Re: Intel 82576 Gigabit on Debian 7 slow speed.
On 12/21/2015 11:20 PM, Mimiko wrote:
One [RAID] channel is connected to 8 x 2TB the other channel to 8 x 1TB.
What is the part number of your cables?
JBOD for software raid [on Wheezy].
I thought the 'zpool create ...' invocation showed all 16 drives in one
raidz2 pool (?). This is not the same as JBOD.
The windows server uses HW RAID6.
Hardware RAID is generally considered to be faster than software RAID,
but the latter offers more opportunities for tuning.
[Drives are enclosed] in same server 2U.
[Drives get power] from same power as MB.
Toshiba 2TB 3.5" MG03ACA200 SATA and Toshiba 1TB 3.5" MG03ACA100 SATA.
Okay.
http://toshiba.semicon-storage.com/us/product/storage-products/enterprise-hdd.html
[Disconnect RAID and benchmark system SSD's] is impossible for now.
Schedule a maintenance window.
> I don't understand the meaning of ["do you know if your amount of RAM
> is too much, too little, or just right?"]. More RAM is better, but
> this is what we have on this server.
What I'm suggesting is that you find some metric(s) to tell you how much
memory Linux, ZFS, and Samba are using:
- Too little memory is bad, for reasons we all already know.
- Too much memory is a waste -- the extra memory could be put into
another machine where it is needed.
zfs list
NAME USED AVAIL REFER MOUNTPOINT
zfspool 11.5T 39.7G 335K none
Ouch. You need to free up space soon, or you're going to have a disaster.
Slow throughput is a symptom of full drives.
I suspect that your 'zpool create ...' invocation with differing drive
sizes resulted in ZFS treating all the drives as the same size as the
smallest drive -- e.g. 16 @ 1 TB. So, it appears that raidz2 cost you 4
TB, or 25% of your raw space.
Windows Server 2008 R2 x64
Okay.
Windows server has 48GB RAM and 8 x 2TB HDD and no separate SSD's.
> Windows is on HW RAID6.
> No [software RAID or dynamic disks].
You are making an apples to oranges comparison.
48 GB vs. 18 GB -- Linux has 1/3 the RAM
8 drives on 8 channels vs. 16 drives on 8 channels -- Linux has
twice the buss contention.
hardware RAID vs. software RAID -- I don't think the Linux software
RAID is set up optimally
That said, any computer with drives that are 99.6% full is not going to
benchmark well; it's going to crash.
Only one laptop. May be one desktop too. Its easier to setup another
server with same MB but lower disk count and ram.
It's good to have spare hardware for running tests, doing maintenance,
and for emergencies (like now).
So keep in touch. As this is disappointing for Debian to loose to windows in file share.
I think either can perform well, when properly tuned.
There are now around 8 ext4 filesystems with different sizes.
Okay.
> Unfortunately [I am unable to move services off the machine]. Its a
> lot of data. This is only server with lot of disk space.
Been there, done that, and lost data, time, money, credibility,
business, etc..
700Mbit/s is about 80MB/s. So I think its not intel network card the
issue. Something is with samba or zfs.
I agree that Gigabit interfaces should run at close to capacity, but the
iperf numbers you posted previously show otherwise.
David
Reply to: