If I've failed to find this on the mailinglist or in my google searches, I am sorry. However, as I'm experimenting with using mdb for the backend with OpenLDAP-2.4.33 on RHEL 6.3, I'm wondering what am I looking for when I run mdb_stat and it tells me:
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Frank Swasey wrote:
If I've failed to find this on the mailinglist or in my google searches, I am sorry. However, as I'm experimenting with using mdb for the backend with OpenLDAP-2.4.33 on RHEL 6.3, I'm wondering what am I looking for when I run mdb_stat and it tells me:
Huh? I'm wondering what you're looking for when you run mdb_stat. What did you expect to see?
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Today at 4:42am, Howard Chu wrote:
Huh? I'm wondering what you're looking for when you run mdb_stat. What did you expect to see?
I guess I was expecting to see something more like the output of db_stat, which I ran looking for deadlocks and evidence that any limits were starting to be hit so I should tweak the DB_CONFIG file and restart.
Since mdb doesn't have any of those issues, then I guess I'm just really looking for guidance about the use of mdb_stat and what I should be monitoring to be sure that I'm not on the brink of something breaking. Perhaps I have read the existing documentation too quickly. However, so far, I don't think I've found any guidance about how to monitor the back_mdb to stay on top of possible issues.
16.10.2012 21:19, Frank Swasey пишет:
Today at 4:42am, Howard Chu wrote:
Huh? I'm wondering what you're looking for when you run mdb_stat. What did you expect to see?
I guess I was expecting to see something more like the output of db_stat, which I ran looking for deadlocks and evidence that any limits were starting to be hit so I should tweak the DB_CONFIG file and restart.
Since mdb doesn't have any of those issues, then I guess I'm just really looking for guidance about the use of mdb_stat and what I should be monitoring to be sure that I'm not on the brink of something breaking. Perhaps I have read the existing documentation too quickly. However, so far, I don't think I've found any guidance about how to monitor the back_mdb to stay on top of possible issues.
Actually get current storage area usage would be nice. Sorting out "MDB_MAP_FULL: Environment mapsize limit reached" errors is not a good choice.
Frank Swasey wrote:
Today at 4:42am, Howard Chu wrote:
Huh? I'm wondering what you're looking for when you run mdb_stat. What did you expect to see?
I guess I was expecting to see something more like the output of db_stat, which I ran looking for deadlocks and evidence that any limits were starting to be hit so I should tweak the DB_CONFIG file and restart.
Since mdb doesn't have any of those issues, then I guess I'm just really looking for guidance about the use of mdb_stat and what I should be monitoring to be sure that I'm not on the brink of something breaking.
Right. Since MDB is deadlock proof there's no information of that sort to show.
Perhaps I have read the existing documentation too quickly. However, so far, I don't think I've found any guidance about how to monitor the back_mdb to stay on top of possible issues.
There are only two settings to worry about: mapsize and maxreaders. If your maxreaders is greater than the number of slapd threads, you probably don't have to worry about it. For the mapsize, you can just use "du" on the MDB directory to see how much space is in use.
There's really not much more to tell.
These tools are definitely immature though. In the source tree you'll also find mdb_stata.c and mfree.c; their functionality is intended to be merged into a more useful mdb_stat command at some point in the future.
We'll likely also add some function to dump out the contents of the readers table. But the need for these things is pretty low.
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