Re:Migrating a large site from SQL Server to MongoDB - Lesso...
by willvarfar on Sunday November 06, 2011 @03:48PM
(#3203785)
So do you have fsync enabled?
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Re:Migrating a large site from SQL Server to MongoDB - Lesso...
by rfurlan on Sunday November 06, 2011 @03:52PM
(#3203800)
fsync is enabled for the vast majority of calls and it is our default setting. Disabling fsync should be treated as case-by-case optimization IMO
Re:Migrating a large site from SQL Server to MongoDB - Lesso...
by latch on Monday November 07, 2011 @06:28AM
(#3205835)
I assume when people talk about fsync, they actually mean journaling?
I'm not sure if there's ever a good reason to use {fsync: true} vs {j: true}
Re:Migrating a large site from SQL Server to MongoDB - Lesso...
by rfurlan on Monday November 07, 2011 @12:10PM
(#3207097)
Fsync means "wait for acknowledgement after each request", if Fsync is off, all calls are fire-and-forget, no errors are reported. There are a few Fsync levels though, you can use it to make the call block until the data has been relayed to at least N other nodes.
Re:Migrating a large site from SQL Server to MongoDB - Lesso...
by latch on Monday November 07, 2011 @08:23PM
(#3209040)
no, fsync means wait for the data file to be synced to disk. {safe:true} is what you are talking about. {j:true} is probably what yo should be using, {w:majority} is also important, and {fsync:true} is the data file option
I think given that one of the parameters is called "fsync" using "fsync" should mean that.