On Apr 23, 2012, at 10:28 AM, Rich Megginson wrote:
interesting. Does Sun DS have some sort of tuning parameter
for number of values? That is, they may have some threshold
for number of values in an attribute - once the number hits
that threshold, they may switch to using some sort of ADT to
store the values, like a AVL tree or hash table, rather than
the simple linked list used by default.
I've compared the dse.ldif of both servers looking
specifically for attributes that I should transfer from our
production environment to 389. The configurations for major
components are virtually identical and I have seen no
attribute that relates to the number of values in a
multi-valued attribute. I expect that the optimization is a
behind-the-scenes code improvement.
Also during this testing I have noticed a memory leak
when running large quantities of ldapmodify operations.
When I set up a loop to delete and then re-add the
eduPersonEntitlement attribute across 100K entries, I
found that memory consumption continuously increased and
the server crashed after the fifth iteration of this
loop. (And this one really is with ldapmodify and is
not related to my earlier issues with excessively
creating tombstones by deleting and adding entire
entries). Before digging into this too deeply and
making another ticket, I wanted to ask if this had been
noticed and fixed in the 1.2.10 release? I am using the
default 126.96.36.199 release. I'm guessing it hasn't since I
didn't see it in the release notes.
Try increasing your nsslapd-cachememsize and monitoring it
closely. Using the size of id2entry.db4 is a good place to
start, but that will not be enough.
Early on in the process of setting up 389 I optimized the
cachememsize. I configured a 12G cache, and the cache usage
after loading all 600K entries is just under 10G. While the
ldapmodify operations are in progress, I am pretty sure I did
not have an increase in the cacheentryusage monitor attribute
under cn=config, but I'd have to re-check to be sure.