php and values not returning from memcached

[sjohnsonlist@feedster.com]

Hi Brad,

stats slabs
STAT 6:chunk_size 64
STAT 6:chunks_per_page 16384
STAT 6:total_pages 1
STAT 6:total_chunks 16384
STAT 6:used_chunks 16383
STAT 6:free_chunks 1
STAT 6:free_chunks_end 15648
STAT 7:chunk_size 128
STAT 7:chunks_per_page 8192
STAT 7:total_pages 1
STAT 7:total_chunks 8192
STAT 7:used_chunks 8192
STAT 7:free_chunks 0
STAT 7:free_chunks_end 7211
STAT 8:chunk_size 256
STAT 8:chunks_per_page 4096
STAT 8:total_pages 1
STAT 8:total_chunks 4096
STAT 8:used_chunks 4096
STAT 8:free_chunks 0
STAT 8:free_chunks_end 3204
STAT 9:chunk_size 512
STAT 9:chunks_per_page 2048
STAT 9:total_pages 1
STAT 9:total_chunks 2048
STAT 9:used_chunks 2048
STAT 9:free_chunks 0
STAT 9:free_chunks_end 1092
STAT 10:chunk_size 1024
STAT 10:chunks_per_page 1024
STAT 10:total_pages 1
STAT 10:total_chunks 1024
STAT 10:used_chunks 1024
STAT 10:free_chunks 0
STAT 10:free_chunks_end 60
STAT 11:chunk_size 2048
STAT 11:chunks_per_page 512
STAT 11:total_pages 1
STAT 11:total_chunks 512
STAT 11:used_chunks 512
STAT 11:free_chunks 0
STAT 11:free_chunks_end 210
STAT 12:chunk_size 4096
STAT 12:chunks_per_page 256
STAT 12:total_pages 1
STAT 12:total_chunks 256
STAT 12:used_chunks 256
STAT 12:free_chunks 0
STAT 12:free_chunks_end 73
STAT 13:chunk_size 8192
STAT 13:chunks_per_page 128
STAT 13:total_pages 1
STAT 13:total_chunks 128
STAT 13:used_chunks 128
STAT 13:free_chunks 0
STAT 13:free_chunks_end 57
STAT 14:chunk_size 16384
STAT 14:chunks_per_page 64
STAT 14:total_pages 1
STAT 14:total_chunks 64
STAT 14:used_chunks 64
STAT 14:free_chunks 0
STAT 14:free_chunks_end 51
STAT 15:chunk_size 32768
STAT 15:chunks_per_page 32
STAT 15:total_pages 1
STAT 15:total_chunks 32
STAT 15:used_chunks 32
STAT 15:free_chunks 0
STAT 15:free_chunks_end 29
STAT 16:chunk_size 65536
STAT 16:chunks_per_page 16
STAT 16:total_pages 1
STAT 16:total_chunks 16
STAT 16:used_chunks 16
STAT 16:free_chunks 0
STAT 16:free_chunks_end 15
STAT 17:chunk_size 131072
STAT 17:chunks_per_page 8
STAT 17:total_pages 1
STAT 17:total_chunks 8
STAT 17:used_chunks 8
STAT 17:free_chunks 0
STAT 17:free_chunks_end 7
STAT active_slabs 12
STAT total_malloced 12582912

That's from one of my servers and here's from the other one heavily in use:

stats slabs
STAT 6:chunk_size 64
STAT 6:chunks_per_page 16384
STAT 6:total_pages 1
STAT 6:total_chunks 16384
STAT 6:used_chunks 16383
STAT 6:free_chunks 1
STAT 6:free_chunks_end 15751
STAT 7:chunk_size 128
STAT 7:chunks_per_page 8192
STAT 7:total_pages 1
STAT 7:total_chunks 8192
STAT 7:used_chunks 8191
STAT 7:free_chunks 1
STAT 7:free_chunks_end 7167
STAT 8:chunk_size 256
STAT 8:chunks_per_page 4096
STAT 8:total_pages 1
STAT 8:total_chunks 4096
STAT 8:used_chunks 4096
STAT 8:free_chunks 0
STAT 8:free_chunks_end 3265
STAT 9:chunk_size 512
STAT 9:chunks_per_page 2048
STAT 9:total_pages 1
STAT 9:total_chunks 2048
STAT 9:used_chunks 2047
STAT 9:free_chunks 1
STAT 9:free_chunks_end 1131
STAT 10:chunk_size 1024
STAT 10:chunks_per_page 1024
STAT 10:total_pages 1
STAT 10:total_chunks 1024
STAT 10:used_chunks 1023
STAT 10:free_chunks 1
STAT 10:free_chunks_end 641
STAT 11:chunk_size 2048
STAT 11:chunks_per_page 512
STAT 11:total_pages 1
STAT 11:total_chunks 512
STAT 11:used_chunks 511
STAT 11:free_chunks 1
STAT 11:free_chunks_end 224
STAT 12:chunk_size 4096
STAT 12:chunks_per_page 256
STAT 12:total_pages 1
STAT 12:total_chunks 256
STAT 12:used_chunks 256
STAT 12:free_chunks 0
STAT 12:free_chunks_end 106
STAT 13:chunk_size 8192
STAT 13:chunks_per_page 128
STAT 13:total_pages 1
STAT 13:total_chunks 128
STAT 13:used_chunks 127
STAT 13:free_chunks 1
STAT 13:free_chunks_end 72
STAT 14:chunk_size 16384
STAT 14:chunks_per_page 64
STAT 14:total_pages 1
STAT 14:total_chunks 64
STAT 14:used_chunks 63
STAT 14:free_chunks 1
STAT 14:free_chunks_end 42
STAT 15:chunk_size 32768
STAT 15:chunks_per_page 32
STAT 15:total_pages 1
STAT 15:total_chunks 32
STAT 15:used_chunks 31
STAT 15:free_chunks 1
STAT 15:free_chunks_end 24
STAT active_slabs 10
STAT total_malloced 10485760


Oh and it is memcached 1.1.9.  That's the standard one emerged by gentoo
and I'm starting to wonder if this is version hell now that I see I'm
dated back to 2003.  Time for an upgrade ...

Scott

> New items push old items out, unless you use the command line option to
> override that.  Try pasting to us the results of "stats slabs" so we can
> see how much memory is actually being used, and how.
>
> flush_all won't make the results of "stats" change.  It just sets an
> internal time that items have to be newer than to be returned with "get"
> or "get_multi".  So they'll be flushed lazily when they're gotten later.
>
> - Brad
>
>
> On Wed, 2 Jun 2004 sjohnsonlist@feedster.com wrote:
>
>> Hi all,
>>
>> Note: 1st post here so please excuse obvious stupidity but I did read
>> through the api docs and server docs w/o seeing anything.
>>
>> I'm running memcached across 3 servers on gentoo linux, kernel 2.6.5
>> environment (400 megs ram, 100 megs ram, 300 megs ram).
>>
>> What I'm doing is writing a cache loader to pre-populate a cache of data
>> pulled from a mysql table.  And what I'm finding is that caching a large
>> number of items is leaving a handful without values.
>>
>> My code is using the php API from this:
>> http://www.danga.com/memcached/dist/php-memcached-1.0.10.tar.gz
>>
>> Basically all I do is loop over my database and call $memc->set($key,
>> $value, $expire) and then kill the job if $memc returns false.  It never
>> dies so memcache seems to be accepting all my objects fine.  That works
>> fine and here's my internal diagnostics at the end of the job:
>>
>> Total size = 10795847 (this is the sum of the string lengths I loaded)
>> 22734 total objects loaded (this is the total # of keys I sent to
>> memcache)
>>
>> Now when I go to retrieve the content, I get this result:
>>
>> Key=|raw_content_47519384|
>> err=No value found for key raw_content_47519384
>>
>> But I know this was set correctly or my code would have died (and my
>> logs
>> show it was set correctly).  My guess is that objects are being expired
>> from the cache as new objects come in but I am setting a 5 day
>> expiration
>> time as measured by a time() + (5*86400) value. And this doesn't seem to
>> be enough data to overflow a cache of this size.
>>
>> Here are my stats from the server:
>> stats
>> STAT pid 25901
>> STAT uptime 503
>> STAT time 1086201062
>> STAT version 1.1.9
>> STAT rusage_user 0:118981
>> STAT rusage_system 0:190970
>> STAT curr_items 4395
>> STAT total_items 4395
>> STAT bytes 2498844
>> STAT curr_connections 1
>> STAT total_connections 5094
>> STAT connection_structures 4
>> STAT cmd_get 697
>> STAT cmd_set 4395
>> STAT get_hits 498
>> STAT get_misses 199
>> STAT bytes_read 2454699
>> STAT bytes_written 338016
>> STAT limit_maxbytes 524288000
>> END
>> flush_all
>> ERROR
>>
>> Interestingly I'm finding that the flush_all command isn't working.
>> That
>> feeds very, very wrong.
>>
>> Comments ?  Thanks in advance.
>>
>> Scott
>>
>>
>>
>>
>>
>>
>