Hi,

I’m running openproject from the develop branch together with memcached. I’m not very familiar with memcache but it looks like it’s not used in a way that would really speed up performance.
I started investigating because openproject (served with apache+passenger) is quite slow (~8 sec. waiting for a workpackage saved filter).

Below is the output of the current memcached “stats” cmd after a few minutes clicking through the UI.
What makes me wonder:

- Why does memcached store only 6 current_items ?

root@moewe:~# echo 'stats' | nc localhost 11211
STAT pid 27234
STAT uptime 1395
STAT time 1486337939
STAT version 1.4.21
STAT libevent 2.0.21-stable
STAT pointer_size 64
STAT rusage_user 0.036000
STAT rusage_system 0.052000
STAT curr_connections 8
STAT total_connections 32
STAT connection_structures 10
STAT reserved_fds 20
STAT cmd_get 240
STAT cmd_set 111
STAT cmd_flush 0
STAT cmd_touch 0
STAT get_hits 233
STAT get_misses 7
STAT delete_misses 0
STAT delete_hits 2
STAT incr_misses 0
STAT incr_hits 0
STAT decr_misses 0
STAT decr_hits 0
STAT cas_misses 0
STAT cas_hits 0
STAT cas_badval 0
STAT touch_hits 0
STAT touch_misses 0
STAT auth_cmds 0
STAT auth_errors 0
STAT bytes_read 58612
STAT bytes_written 661715
STAT limit_maxbytes 536870912
STAT accepting_conns 1
STAT listen_disabled_num 0
STAT threads 4
STAT conn_yields 0
STAT hash_power_level 16
STAT hash_bytes 524288
STAT hash_is_expanding 0
STAT malloc_fails 0
STAT bytes 13021
STAT curr_items 6
STAT total_items 111
STAT expired_unfetched 0
STAT evicted_unfetched 0
STAT evictions 0
STAT reclaimed 0
STAT crawler_reclaimed 0
STAT lrutail_reflocked 0

Listing the current items with memcache_list_names.rb :

~/memcache# ./memcache_list_names.rb


|      id |                      expires |        bytes | cache_key                                                                                                                                         |
|       6 |    2017-02-06 00:14:44 +0100 |          192 | _session_id:9a91983c67eaa8076c10c36bf022d9b4                                                                                                      |
|       6 |    2017-02-06 00:14:44 +0100 |          192 | _session_id:2037e4d008d3d388fde0e7670dcfb998                                                                                                      |
|       7 |    2017-02-06 02:28:09 +0100 |          224 | check_memcached                                                                                                                                   |
|      17 |    2017-02-06 00:14:44 +0100 |         3377 | openproject/6.2.0.e9a9b6cc7/help_top_menu_node/de/{:href=>"https://www.openproject.org/help/user-guides", :label=>"homescreen.links.user_guides"} |
|      17 |    2017-02-06 00:14:44 +0100 |         3141 | openproject/6.2.0.e9a9b6cc7/help_top_menu_node/en/{:href=>"https://www.openproject.org/help/user-guides", :label=>"homescreen.links.user_guides"} |
|      19 |    2017-02-06 00:14:44 +0100 |         5061 | /openproject/settings/all/1485608908