[lustre-discuss] GID only mapping in 2.8.60?

[Dilger, Andreas]

Actually, the nodemap feature will work with any client, since it is only affecting lookups on the MDS and quota on the OSS. 

It probably would take less time for you to implement the flag feature than the time it is taking to create the thousands of UID entries. While I think it should scale very large, I don't think we have tested the 1M or so entries you are creating. The good news is that since this is using a hash table on the server it shouldn't hurt performance too much. 

Let us know how many you finally create, and how it is working with so many entries. 

Cheers, Andreas

> On Nov 4, 2016, at 21:06, Stephane Thiell <sthiell at stanford.edu> wrote:
> 
> Hi Andreas,
> 
>> I agree that allowing ranges of UID/GID to be mapped would be very useful in different sites, instead of creating so many separate IDs.
>> 
>> In your case, it might be simplest to add a flag to the nodemap like "identity_uid" that avoids the need for UID maps, and then only install GID maps and a select number of UID maps as needed?  It might also be worthwhile to add an "identity_gid" flag at the same time, even if you aren't using it at this time.
> 
> Yes indeed, something like identity_{uid,gid}_unknown would be great (to match another existing flag named ‘deny_unknown’ for example).
> 
> For now, I have been able to create many separate idmaps (it’s slow though) and so far it works, even with 2.7 clients!
> 
> It only takes a few tens of MB on the servers, so no big deal, but I am a bit concerned about MD ops performance with such a big map.
> 
> Thanks to the developers for this useful feature that will help many sites.
> 
> Best,
> Stephane
> 
>