ntdb for Samba 4.2?

Volker Lendecke Volker.Lendecke at SerNet.DE
Wed Mar 19 00:15:09 MDT 2014


On Wed, Mar 19, 2014 at 02:48:33PM +1030, Rusty Russell wrote:
> Meanwhile, there's no demand to drive it.  TDB has problems, but scaling
> over 3GB isn't the main one.  The locking speed has been greatly
> improved by the addition of inline mutexes; and so you won't notice
> freelist contention as much.  And using dbwrap means the new API doesn't
> even make the code cleaner.

Even with mutexes you do notice freelist contention. The
real kick for this in our tests is the patch from
yesterday: With TDB_VOLATILE we keep some dead records per
chain, and while the freelist is blocked we go fishing for
dead records in other chains. Essentially, this turns each
chain into a small freelist. This together with mutexes
really, really rocks. No futex syscalls around anymore even
for heavily loaded servers. :-)

Volker

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