[Zope] replication (was Zope: 5.4, jboss 0.3 million hits wit h google)

[Toby Dickenson]

On Thursday 13 February 2003 3:46 am, sean.upton@uniontrib.com wrote:
> I suppose that one issue is that packing in DirectoryStorage uses snapshots
> so that using something like rsync or cpio+find+nfs for incremental
> backup/replication to a peer ZSS would need to use snapshots.  You can't do
> this while packing though, because packing uses snapshots.  

Correct. I am planning to attack this in three directions:
1. changing packing so that it doesnt keep the storage in snapshot mode during 
the whole packing process.
2. A good choice of linux kernel patches. Chris Mason's latest reiserfs 
patches help *alot*, but I am not yet willing to trust the 2.4.20 kernel in 
production.
3. Speeding up packing. Version 1.1 has an experimental option that is 
somewhat faster, but has a disk space overhead and leaks memory :-( I am 
waiting to see whether this has much benefit on a patched kernel before 
polishing this for production use.

> So a
> replication tool that uses normal history isn't prohibited during packing.

The replication tool currently does need to force the storage into snapshot 
mode. Yes, this means you cant replicate and pack at the same time.



-- 
Toby Dickenson
http://www.geminidataloggers.com/people/tdickenson