On Feb 20, 2009, at 6:03 AM, Pascal Borghino wrote:
> I am currently compacting it... even if 'Compaction rewrites the
> database file, removing outdated document revisions and deleted
> documents'... no document should be outdate neither deleted...
In addition to the sparseness of the file, another reason for the size
difference might be obsolete b-tree nodes. The file is append-only, so
any time a b-tree changes, the old nodes remain in the file. If you've
done a large number of individual insertions, that space might be
significant. (Probably not gigabytes, though.)
robert.newson@gmail.com wrote:
> I find the actual
> consumed space is far, far less that 'ls' shows. CouchDB .couch files
> are very sparse, large gaps of unwritten data, ostensibly to keep
> btree and document items separate, but these 'holes' vanish after
> compaction, even if you have zero updates and deletes.
Hm. But not all filesystems support sparse files. HFS+, the Mac OS
filesystem, doesn't. (Does NTFS?) Is there an option to suppress the
gaps?
—Jens
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