[Samba] Repacking database from v1 to v2 format: how long does it take?

[Francesco Malvezzi]

On 23/09/2019 20:41, Andrew Bartlett wrote:
> On Mon, 2019-09-23 at 11:25 +0200, Francesco Malvezzi via samba wrote:
>> hi all,
>>
>> I updated a small domain with 8k object to samba-4.11.0 and the
>> database
>> conversion from v1 to v2 didn't take a noticeable time.
>>
>> On the other hand, in a larger domain with 67k object, where the
>> sudo ./bin/samba-tool dbcheck --cross-ncs --fix
>> takes ~40 minutes, 2 hours and half were not enough to complete the
>> conversion.
>>
>> Is it a couple of hours something expected if dbcheck takes so much
>> time?
>>
>> Is it maybe my AD db to be pathologic?
> 
> Ouch!  We did not see such long runtimes during our testing, which is
> why no major warnings were made.  Are you on TDB or LMDB?  Does the
> host have enough RAM?

It's TDB. I am unaware of the chance to convert to LMDB.

> 
> At your scale I would suggest say 10G, being 4GB for the main TDB, 4GB
> for the transaction copy for the repack, and extra.

It's close: 8GB, but while doing repack memory's usage was never higher
than 20%; it was high on cpu, one core out of two was stuck at 100%.
According to top, there was no iowait, so I supposed it was not a memory
issue.

I'm going to check more carefully,
> 
> Sorry!

no problem,

thank you,

franz