Thanks Brian, Will it be possible for this patch to be backported to libmemcached 0.26 which is what I am using?
Regards, Nikhils On Tue, Apr 14, 2009 at 7:49 PM, Brian Aker <[email protected]> wrote: > > Hi! > > I've applied this patch. It should be pushed within the hour. > > Thanks, > -Brian > > > On Apr 14, 2009, at 3:50 AM, Nikhils wrote: > > Hi Brian, >> >> A careful perusal of the memcached_mget_by_key() function revealed the >> bug. >> >> The code was generating the serverid by using the master key first. >> However if the serverid was 0, the following check was causing re-evaluation >> of the serverid by using the buffer key leading to the query being sent to >> another server: >> >> if (master_server_key) /* if the serverid had evaluated to zero, we go >> to else */ >> server_key= master_server_key; >> else >> server_key= memcached_generate_hash(ptr, keys[x], key_length[x]); >> >> After fixing this, the *_by_key logic appears to be working just fine. >> >> Please find attached, a patch (diff -c format) which fixes this. >> >> Regards, >> Nikhils >> >> On Tue, Apr 14, 2009 at 12:27 PM, Nikhils <[email protected]> wrote: >> Hi, >> >> I recently shifted to using the memcached_get/set_by_key APIs. The trouble >> is that even after warming the cache with all of the content, a subsequent >> query to fetch the key/value pair fails with a not found error. I am seeing >> this behaviour in a 2-node memcached cluster. >> >> Its occurring consistently and on reverting back to using the normal >> memcached_get/set APIs, the key/value pairs can be retrieved appropriately! >> However I do need to use these by_key APIs for my data consistency logic. >> >> I have added appropriate logging information in my C code (am linking to >> libmemcached 0.27) and confirmed that the master key is the same in both >> set_by_key/get_by_key calls. >> >> Anything obvious that I am missing? Has anyone observed such dubious >> behaviour before with these by_key calls? Comments appreciated. >> >> Regards, >> Nikhils >> >> <libmemcached_mget_by_key_bug.patch> >> > > -- > _______________________________________________________ > Brian "Krow" Aker, brian at tangent.org > Seattle, Washington > http://krow.net/ <-- Me > http://tangent.org/ <-- Software > _______________________________________________________ > You can't grep a dead tree. > > > >
