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| Florian Weimer... |
 Posted: Thu Jul 17, 2008 12:40 am |
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Guest
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I tested this again after a couple of years, and the behavior doesn't
seem to have changed: If a Berkeley DB database is written using TDS
with a reasonably sized cache, data is written from the cache to the
file system in what a appears to be a random fashion. Apparently, a lot
of holes are created, which are then filled. This degrades file system
performance and makes hot backups somewhat difficult (because the read
performance is a fraction of that what can actually achieved).
Is there still no way to preallocate the contents of B-tree files?
(Without TDS, the problem disappears, it seems to be related TDS or the
cache size.) |
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| wawawawa... |
| Posted: Mon Jul 21, 2008 4:36 am |
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post to http://forums.oracle.com/forums/forum.jspa?forumID=271
they have bdb dev taking questions
On Jul 16, 12:40 pm, Florian Weimer <f... at (no spam) deneb.enyo.de> wrote:
Quote: I tested this again after a couple of years, and the behavior doesn't
seem to have changed: If a Berkeley DB database is written using TDS
with a reasonably sized cache, data is written from the cache to the
file system in what a appears to be a random fashion. Apparently, a lot
of holes are created, which are then filled. This degrades file system
performance and makes hot backups somewhat difficult (because the read
performance is a fraction of that what can actually achieved).
Is there still no way to preallocate the contents of B-tree files?
(Without TDS, the problem disappears, it seems to be related TDS or the
cache size.) |
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| Florian Weimer... |
| Posted: Mon Jul 21, 2008 1:33 pm |
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Guest
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* wawawawa:
Some Sleepycat folks used to be around here, too.
Registering for forums is always a bit of a hassle, and they require
tons of informatio$n. |
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| Florian Weimer... |
| Posted: Mon Jul 21, 2008 1:33 pm |
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Guest
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* wawawawa:
Some Sleepycat folks used to be around here, too.
Registering for forums is always a bit of a hassle, and they require
tons of information. |
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