It is interesting that spymemcached client stores items less effective.
Under the same conditions in 128Mb memcached instance:
spymemached: STAT curr_items 317886
danga: STAT curr_items 491882
Danga memcached is initialized with the following parameters:
memCachedClient = new MemCachedClient();
memCachedClient.setSanitizeKeys(false);
memCachedClient.setCompressEnable(false);
memCachedClient.setPrimitiveAsString(false);
Spymemcached uses defaults.
--
Alexander Zaitsev
AMG Lab Sarl
Kristian Eide wrote:
I recently had to make a choice of which memcached Java library to use
and I did some simple informal benchmarking between the Whalin client
and 'spymemcached'. While limited in scope I think the results are
quite clear.
My test consisted of writing 2000 values and then reading them back; I
repeated this for various sized objects. I used only a single
Memcached Java object with a compression threshold of 16KB. I did not
adjust any of the defaults.
The tests were run on Java 1.6, under Mac OS X, and a single instance
of memcached 1.2.4 on localhost with 64MB of memory. The computer has
4 CPU cores.
Here are the results for the Whalin client (numbers are in milliseconds):
N: 2000 Size: 2 Store: 980 Fetch: 1372 kbPerSecond: 2
FetchesPerSecond: 1457
N: 2000 Size: 4 Store: 596 Fetch: 1245 kbPerSecond: 6
FetchesPerSecond: 1605
N: 2000 Size: 9 Store: 503 Fetch: 1122 kbPerSecond: 15
FetchesPerSecond: 1782
N: 2000 Size: 19 Store: 391 Fetch: 1007 kbPerSecond: 36
FetchesPerSecond: 1984
N: 2000 Size: 39 Store: 390 Fetch: 1013 kbPerSecond: 75
FetchesPerSecond: 1973
N: 2000 Size: 81 Store: 363 Fetch: 992 kbPerSecond: 159
FetchesPerSecond: 2015
N: 2000 Size: 168 Store: 370 Fetch: 978 kbPerSecond: 335
FetchesPerSecond: 2043
N: 2000 Size: 350 Store: 357 Fetch: 967 kbPerSecond: 706
FetchesPerSecond: 2067
N: 2000 Size: 729 Store: 375 Fetch: 1004 kbPerSecond: 1416
FetchesPerSecond: 1990
N: 2000 Size: 1516 Store: 391 Fetch: 1051 kbPerSecond: 2815
FetchesPerSecond: 1901
N: 2000 Size: 3154 Store: 398 Fetch: 1034 kbPerSecond: 5956
FetchesPerSecond: 1933
N: 2000 Size: 6561 Store: 426 Fetch: 1072 kbPerSecond: 11946
FetchesPerSecond: 1864
N: 2000 Size: 13647 Store: 545 Fetch: 1010 kbPerSecond: 26369
FetchesPerSecond: 1978
N: 2000 Size: 28388 Store: 2321 Fetch: 1346 kbPerSecond: 41172
FetchesPerSecond: 1485
N: 2000 Size: 59049 Store: 3681 Fetch: 1347 kbPerSecond: 85571
FetchesPerSecond: 1483
Total: 28666 ms
And here are the results with 'spymemcached':
N: 2000 Size: 2 Store: 479 Fetch: 1081 kbPerSecond: 3
FetchesPerSecond: 1849
N: 2000 Size: 4 Store: 196 Fetch: 831 kbPerSecond: 9 FetchesPerSecond:
2405
N: 2000 Size: 9 Store: 127 Fetch: 624 kbPerSecond: 28
FetchesPerSecond: 3203
N: 2000 Size: 19 Store: 56 Fetch: 533 kbPerSecond: 69
FetchesPerSecond: 3750
N: 2000 Size: 39 Store: 66 Fetch: 534 kbPerSecond: 142
FetchesPerSecond: 3740
N: 2000 Size: 81 Store: 65 Fetch: 470 kbPerSecond: 336
FetchesPerSecond: 4252
N: 2000 Size: 168 Store: 41 Fetch: 452 kbPerSecond: 725
FetchesPerSecond: 4424
N: 2000 Size: 350 Store: 42 Fetch: 449 kbPerSecond: 1522
FetchesPerSecond: 4454
N: 2000 Size: 729 Store: 46 Fetch: 457 kbPerSecond: 3112
FetchesPerSecond: 4371
N: 2000 Size: 1516 Store: 50 Fetch: 449 kbPerSecond: 6594
FetchesPerSecond: 4454
N: 2000 Size: 3154 Store: 57 Fetch: 442 kbPerSecond: 13918
FetchesPerSecond: 4518
N: 2000 Size: 6561 Store: 131 Fetch: 476 kbPerSecond: 26876
FetchesPerSecond: 4194
N: 2000 Size: 13647 Store: 227 Fetch: 495 kbPerSecond: 53830
FetchesPerSecond: 4039
N: 2000 Size: 28388 Store: 1452 Fetch: 1044 kbPerSecond: 53074
FetchesPerSecond: 1914
N: 2000 Size: 59049 Store: 2388 Fetch: 1131 kbPerSecond: 101952
FetchesPerSecond: 1768
Total: 14909 ms
The total time is almost half with 'spymemcached'. However, the
results get even more interesting when you use multiple threads. I
repeated the test with 4 threads and the total time for the Walins
client increased to 101415 ms, while 'spymemcached' only increased to
29535. Perhaps you could get better performance out of the Walins
client by tweaking some settings, but it does seem that 'spymemcached'
is the way to go if you care at all about performance. The async set
can be especially helpful.
I did not look at the CPU usage while the test was running, but I
would expect that 'spymemcached' has the edge here as well.
