memcacheDB using OpenLDAP MDB

[Howard Chu]

For anyone interested, there's now a port of memcacheDB using OpenLDAP's MDB (memory-mapped database) available on https://gitorious.org/mdb/memcachedb in the branch "mine" (the master branch is just an import of the original memcachedb code from SVN).

MDB is several times faster than BerkeleyDB for reads, and has a much smaller footprint. You can read more about MDB here:

http://highlandsun.com/hyc/mdb/

[Howard Chu]

On Monday, September 17, 2012 8:35:22 AM UTC-7, Howard Chu wrote:

For anyone interested, there's now a port of memcacheDB using OpenLDAP's MDB (memory-mapped database) available on https://gitorious.org/mdb/memcachedb in the branch "mine" (the master branch is just an import of the original memcachedb code from SVN).

Is memcachetest actually reliable? It seems to be returning odd results for "max".
 
BDB 4.7
hyc@ada:/home/software/memcachetest$ ./memcachetest -c 100000
Average with 1 threads
Get operations:
     #of ops.       min       max       avg   max90th   max95th   max99th
        66916     50 us     37 ms     92 us    109 us    112 us    119 us

Set operations:
     #of ops.       min       max       avg   max90th   max95th   max99th
        33084     71 us    229 ms    247 us    176 us    182 us    198 us

Usr:  0.496031
Sys:  3.536221
Tot: 17.175638
Server time:
Usr:  5.632352
Sys:  3.968248
Total gets: 0
Total sets: 10000
hyc@ada:/home/software/memcachetest$ ./memcachetest -c 100000 -t 4
Average with 4 threads
Get operations:
     #of ops.       min       max       avg   max90th   max95th   max99th
        67097     56 us    442 us    102 us    130 us    139 us    160 us

Set operations:
     #of ops.       min       max       avg   max90th   max95th   max99th
        32903     84 us    336 ms    655 us    316 us    351 us    437 us

Usr:  0.924057
Sys:  3.684230
Tot:  8.662194
Server time:
Usr:  6.292393
Sys:  4.076255
Total gets: 0
Total sets: 10000

MDB
hyc@ada:/home/software/memcachetest$ ./memcachetest -c 100000
Average with 1 threads
Get operations:
     #of ops.       min       max       avg   max90th   max95th   max99th
        66916     39 us    392 us     58 us     65 us     67 us     74 us

Set operations:
     #of ops.       min       max       avg   max90th   max95th   max99th
        33084     55 us    396 us     77 us     87 us     90 us    100 us

Usr:  0.648040
Sys:  3.496218
Tot:  7.489147
Server time:
Usr:  1.420089
Sys:  3.004187
Total gets: 0
Total sets: 10000
hyc@ada:/home/software/memcachetest$ ./memcachetest -c 100000 -t 4
Average with 4 threads
Get operations:
     #of ops.       min       max       avg   max90th   max95th   max99th
        67143     41 us    392 us     64 us     75 us     80 us     89 us

Set operations:
     #of ops.       min       max       avg   max90th   max95th   max99th
        32857     70 us    517 us    127 us    176 us    193 us    230 us

Usr:  0.872054
Sys:  3.708231
Tot:  3.18446744073709520189
Server time:
Usr:  2.644165
Sys:  3.224201
Total gets: 0
Total sets: 10000

memcached 1.2.0
hyc@ada:/home/software/memcachetest$ ./memcachetest -c 100000
Average with 1 threads
Get operations:
     #of ops.       min       max       avg   max90th   max95th   max99th
        66916     37 us    376 us     56 us     63 us     65 us     71 us

Set operations:
     #of ops.       min       max       avg   max90th   max95th   max99th
        33084     45 us    369 us     59 us     65 us     66 us     69 us

Usr:  0.568035
Sys:  3.500218
Tot:  7.18446744073709103524
Server time:
Usr:  0.888055
Sys:  2.832177
Total gets: 0
Total sets: 10000
hyc@ada:/home/software/memcachetest$ ./memcachetest -c 100000 -t 4
Average with 4 threads
Get operations:
     #of ops.       min       max       avg   max90th   max95th   max99th
        67023     23 us   2411 us    106 us    168 us    178 us    195 us

Set operations:
     #of ops.       min       max       avg   max90th   max95th   max99th
        32977     24 us   1453 us    104 us    162 us    170 us    184 us

Usr:  0.852053
Sys:  3.280205
Tot:  3.167461
Server time:
Usr:  0.476030
Sys:  2.336146
Total gets: 0
Total sets: 10000