NSA-320 disk performance on Kernel 4.4 Kirkwood (no replies)

andsol Wrote:
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> some performance data ... trimmed from post
> Processor goes up to 50%, and results are better on small data.


I have NSA-320 w/ 2 3TB WD REDs in RAID1 booted from USB stick and am on 4.4 kernel and Jessie here is what I'm seeing.
I realize this isn't apples to apples for your 1 drive NSA-325v2 but maybe this will give you some data point you were looking for.

Stock setting:

IQ2700i# cat /sys/block/sda/queue/scheduler
noop deadline [cfq]
IQ2700i# cat /sys/block/sdb/queue/scheduler
noop deadline [cfq]
IQ2700i# cat /sys/block/md0/queue/scheduler
none

The initial tests ran slow, but the follow up ones were faster.
I never noticed CPU going above 70% during this... (watching TOP for this so could be off a bit)

IQ2700i# hdparm -Tt /dev/sda
/dev/sda:
 Timing cached reads:   578 MB in  2.00 seconds = 288.75 MB/sec
 Timing buffered disk reads: 216 MB in  3.02 seconds =  71.53 MB/sec

IQ2700i# hdparm -Tt /dev/sdb
/dev/sdb:
 Timing cached reads:   576 MB in  2.00 seconds = 287.58 MB/sec
 Timing buffered disk reads: 312 MB in  3.01 seconds = 103.62 MB/sec

IQ2700i# hdparm -Tt /dev/sda
/dev/sda:
 Timing cached reads:   388 MB in  2.00 seconds = 194.00 MB/sec <====== this one was 100MB/s slower for some reason compared to the rest.
 Timing buffered disk reads: 332 MB in  3.02 seconds = 109.79 MB/sec

IQ2700i# hdparm -Tt /dev/sdb
/dev/sdb:
 Timing cached reads:   574 MB in  2.00 seconds = 286.39 MB/sec
 Timing buffered disk reads: 362 MB in  3.01 seconds = 120.39 MB/sec

IQ2700i# hdparm -Tt /dev/md0
/dev/md0:
 Timing cached reads:   556 MB in  2.00 seconds = 278.03 MB/sec
 Timing buffered disk reads: 382 MB in  3.01 seconds = 126.97 MB/sec

IQ2700i# hdparm -Tt /dev/md0
/dev/md0:
 Timing cached reads:   544 MB in  2.00 seconds = 271.42 MB/sec
 Timing buffered disk reads: 384 MB in  3.02 seconds = 127.11 MB/sec

Here is the 'dd' testing:

IQ2700i# time sh -c "dd if=/dev/zero of=testfile bs=100k count=1k && sync"
104857600 bytes (105 MB) copied, 1.39 s, 75.4 MB/s
0.00s user 0.91s system 49% cpu 1.829 total

Swapped out to a 1M block size for a 1Gb file, was slightly slower (60MB/s vs 75MB/s)

IQ2700i# time sh -c "dd if=/dev/zero of=testfile bs=1M count=1k && sync"
1073741824 bytes (1.1 GB) copied, 17.9524 s, 59.8 MB/s
0.03s user 11.77s system 64% cpu 18.186 total

Reads were pretty nice:

IQ2700i# time sh -c "dd if=testfile of=/dev/null bs=1M"
1073741824 bytes (1.1 GB) copied, 9.1678 s, 117 MB/s
0.01s user 7.13s system 77% cpu 9.181 total

## changed queue scheduler for drives

IQ2700i# echo deadline > /sys/block/sda/queue/scheduler
IQ2700i# echo deadline > /sys/block/sdb/queue/scheduler
IQ2700i# cat /sys/block/sda/queue/scheduler
noop [deadline] cfq
IQ2700i# cat /sys/block/sdb/queue/scheduler
noop [deadline] cfq

Performance is up, also noted CPU getting to mid 90s now (watching TOP for this so could be off a bit)

IQ2700i# hdparm -Tt /dev/sda

/dev/sda:
 Timing cached reads:   550 MB in  2.00 seconds = 275.00 MB/sec
 Timing buffered disk reads: 372 MB in  3.00 seconds = 123.84 MB/sec
IQ2700i# hdparm -Tt /dev/sdb

/dev/sdb:
 Timing cached reads:   538 MB in  2.01 seconds = 268.31 MB/sec
 Timing buffered disk reads: 408 MB in  3.00 seconds = 135.80 MB/sec
IQ2700i# hdparm -Tt /dev/sda

/dev/sda:
 Timing cached reads:   534 MB in  2.00 seconds = 266.89 MB/sec
 Timing buffered disk reads: 430 MB in  3.01 seconds = 142.75 MB/sec
IQ2700i# hdparm -Tt /dev/sdb

/dev/sdb:
 Timing cached reads:   556 MB in  2.01 seconds = 277.28 MB/sec
 Timing buffered disk reads: 416 MB in  3.01 seconds = 138.20 MB/sec
IQ2700i# hdparm -Tt /dev/md0

/dev/md0:
 Timing cached reads:   290 MB in  2.00 seconds = 144.78 MB/sec <==== another outlier 
 Timing buffered disk reads: 420 MB in  3.01 seconds = 139.74 MB/sec
IQ2700i# hdparm -Tt /dev/md0

/dev/md0:
 Timing cached reads:   574 MB in  2.00 seconds = 287.02 MB/sec
 Timing buffered disk reads: 414 MB in  3.01 seconds = 137.58 MB/sec

Also seems to have smoothed out / potentially improved dd testing:
Some of this could be standard deviation though.

IQ2700i# time sh -c "dd if=/dev/zero of=testfile bs=100k count=1k && sync"
104857600 bytes (105 MB) copied, 1.52577 s, 68.7 MB/s
0.01s user 1.05s system 37% cpu 2.804 total

IQ2700i# time sh -c "dd if=/dev/zero of=testfile bs=1M count=1k && sync"
1073741824 bytes (1.1 GB) copied, 17.3699 s, 61.8 MB/s
0.02s user 11.87s system 66% cpu 17.824 total

IQ2700i# time sh -c "dd if=testfile of=/dev/null bs=1M"
1073741824 bytes (1.1 GB) copied, 8.43713 s, 127 MB/s
0.00s user 6.87s system 81% cpu 8.451 total

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Moderator edit: made this its own thread.