From: Fyodor Ustinov <ufm@ufm.su>
To: ceph-devel@vger.kernel.org
Subject: read and write speed.
Date: Tue, 31 May 2011 01:50:28 +0300 [thread overview]
Message-ID: <4DE41F34.8020504@ufm.su> (raw)
Hi!
Fresh 0.28.2 cluster.
Why reading two times slower than the writing by dd, but rados show
different.
(Second question - why rados bench crash on read test?)
root@gate0:/mnt# dd if=/dev/zero of=aaa bs=1024000 count=10000
10000+0 records in
10000+0 records out
10240000000 bytes (10 GB) copied, 64.5598 s, 159 MB/s
root@gate0:/mnt# dd if=aaa of=/dev/null bs=1024000
10000+0 records in
10000+0 records out
10240000000 bytes (10 GB) copied, 122.513 s, 83.6 MB/s
root@gate0:/mnt#
root@gate0:/etc/ceph# rados -p test bench 20 write
Maintaining 16 concurrent writes of 4194304 bytes for at least 20 seconds.
sec Cur ops started finished avg MB/s cur MB/s last lat avg lat
0 0 0 0 0 0 - 0
1 16 47 31 123.966 124 0.445371 0.360663
2 16 82 66 131.967 140 0.160564 0.32065
3 16 111 95 126.637 116 0.116967 0.349943
4 16 142 126 125.97 124 0.176179 0.369969
5 15 169 154 123.17 112 0.12449 0.411138
6 16 202 186 123.971 128 0.175033 0.442003
7 16 241 225 128.541 156 0.163481 0.421575
8 16 271 255 127.47 120 0.162152 0.444525
9 16 305 289 128.415 136 0.100893 0.456108
10 16 337 321 128.371 128 0.107163 0.467081
11 16 370 354 128.698 132 0.147602 0.455438
12 16 400 384 127.971 120 0.163287 0.454927
13 16 433 417 128.279 132 0.176282 0.451909
14 16 459 443 126.544 104 3.02971 0.465092
15 16 492 476 126.906 132 0.183307 0.473582
16 16 523 507 126.722 124 0.170459 0.465038
17 16 544 528 124.208 84 0.160463 0.462053
18 16 574 558 123.973 120 0.10411 0.478344
19 16 607 591 124.395 132 0.126514 0.48624
min lat: 0.095185 max lat: 3.9695 avg lat: 0.488688
sec Cur ops started finished avg MB/s cur MB/s last lat avg lat
20 16 638 622 124.372 124 2.85047 0.488688
Total time run: 20.547165
Total writes made: 639
Write size: 4194304
Bandwidth (MB/sec): 124.397
Average Latency: 0.513493
Max latency: 3.9695
Min latency: 0.095185
root@gate0:/etc/ceph#
root@gate0:/etc/ceph# rados -p test bench 20 seq
sec Cur ops started finished avg MB/s cur MB/s last lat avg lat
0 0 0 0 0 0 - 0
1 16 58 42 167.966 168 0.085676 0.279929
2 16 101 85 169.97 172 0.785072 0.323728
3 16 145 129 171.969 176 0.141833 0.331852
4 16 193 177 176.969 192 0.75847 0.335484
5 15 240 225 179.97 192 0.114137 0.332022
6 16 288 272 181.303 188 0.54563 0.339292
7 16 335 319 182.256 188 0.531714 0.341969
8 16 380 364 181.97 180 0.101676 0.339337
9 16 427 411 182.634 188 0.216583 0.339264
10 16 471 455 181.968 176 0.803917 0.341281
11 16 515 499 181.422 176 0.112194 0.343552
12 16 559 543 180.968 176 0.241835 0.345668
13 16 600 584 179.66 164 0.088883 0.347034
read got -2
error during benchmark: -5
error 5: Input/output error
root@gate0:/etc/ceph#
WBR,
Fyodor.
next reply other threads:[~2011-05-30 22:50 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-05-30 22:50 Fyodor Ustinov [this message]
2011-05-31 2:26 ` read and write speed djlee064
2011-05-31 2:48 ` Henry C Chang
2011-05-31 3:20 ` djlee064
2011-05-31 7:06 ` Henry C Chang
2011-05-31 7:29 ` djlee064
2011-05-31 10:01 ` Fyodor Ustinov
2011-05-31 14:51 ` Gregory Farnum
2011-05-31 15:05 ` Fyodor Ustinov
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