[Csync2] Using a private network

[Lars Ellenberg]

On Mon, Sep 08, 2008 at 09:18:55PM -0600, Sam Howard wrote:

> Directory "1001" has 4,794,446 files and directories (many of them are
> hardlinks to the same data ... dirvish archive).  This leaves me with a
> database size of 6,033,509,376 bytes (wow!).

> real    141m31.822s
> user    15m47.471s
> sys     4m3.219s

> Is anyone using csync2 to keep larger files (388M really isn't that big) in
> sync?

yes.

>  Also, is there an option to as csync2 to retry a connection a few times
> before giving up?

no.

but, which options are you using?
maybe those can be optimized a little.

e.g. you don't need to "-c" (or -x, for that matter) every time.
it is enough to "-u" until there is no more in the "dirty" state.
saves you a lot of traversal and stat()ing.

btw, did you know about /proc/sys/vm/vfs_cache_pressure?
if not, research it...

>  The startup cost is huge, so that would really help a lot.  
> (to put in perspective, of the 141 minute run time, less than 3 minutes elapsed
> after the source-side scan completed and the transfer actually started, and it
> failed on this first non-sync'd file).
> 
> RAM is not an issue, I don't think ... both hosts have >2GB free, dual core
> AMD64, Ubuntu Hardy.

well.
2GB free...
is that before or during csync2 run?

I dare say sqlite performance may be suboptimal
when using a database size exceeding available RAM.

try to work with multiple configs, getting
the database size for each config to a more
manageable level.

-- 
: Lars Ellenberg                
: LINBIT | Your Way to High Availability
: DRBD/HA support and consulting http://www.linbit.com

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