LARGE single-system Cyrus installs?

Andrew McNamara andrewm at
Wed Nov 21 19:25:26 EST 2007

>>> Would'nt it be nice to have a configuration option to completely  
>>> turn off fsync() in Cyrus? If you want, with a BIG WARNING in the  
>>> doc stating NOT TO USE IT unless you know what you doing. :)
>> Its already in imapd.conf(8):
>> skiplist_unsafe
>Well shiver me timbers!  Ya'll rock.

Note, however, that fsync() still serves a purpose with data journalling - 
without it, your application writes may be sitting in buffer cache,
and may be arbitrarily re-ordered before hitting the disk. The fsync()
should not return until the blocks have reached the disk (or journal),
and thus forms a syncronisation point (which is critical for maintaining
sanity of on-disk data structures like skiplists).

Andrew McNamara, Senior Developer, Object Craft

More information about the Info-cyrus mailing list