[Lustre-discuss] Huge numbers of inodes

[Andreas Dilger]

On 2011-05-20, at 10:17 AM, "Sam Bigger" wrote:
> I doubt it. The largest lustre systems are a little over 300 million files
> that are really in existence.
> 
> However, the limits, in terms of just maximum inodes allowed, using 4K per
> inode and a 2TB max MDT size (mirrored 2 copies), only allows for a little
> over 500 million files max.

The theoretical limit is actually 4B inodes for ext3/4.  I don't think anyone has ever tested that. 

In Lustre 2.1 the default inode ratio has been changed to 1 inode per 2048 bytes (formerly 1 per 4096 bytes). That would allow 4B inodes on an 8TB MDT.

This can be used for any version of mkfs.lustre with "--mkfsoptions '-i 2048'". 

You probably also want to use the ext4 ldiskfs and add '-t ext4' to mkfsoptions so that it enables flex_bg to speed up mkfs and fsck time. 

> -----Original Message-----
> From: lustre-discuss-bounces at lists.lustre.org
> [mailto:lustre-discuss-bounces at lists.lustre.org] On Behalf Of Daniel
> Mayfield
> Sent: Friday, May 20, 2011 9:53 AM
> To: lustre-discuss at lists.lustre.org
> Subject: [Lustre-discuss] Huge numbers of inodes
> 
> Does anybody have experience with Lustre filesystems in the 5-10B inode
> range?   What kind of gotchas do you find at that scale?  What are your
> stripe settings like?
> 
> daniel
> 
> ---------------------------------------------------------------
> This email, along with any attachments, is confidential. If you 
> believe you received this message in error, please contact the 
> sender immediately and delete all copies of the message.  
> Thank you.
> 
> _______________________________________________
> Lustre-discuss mailing list
> Lustre-discuss at lists.lustre.org
> http://lists.lustre.org/mailman/listinfo/lustre-discuss
> 
> _______________________________________________
> Lustre-discuss mailing list
> Lustre-discuss at lists.lustre.org
> http://lists.lustre.org/mailman/listinfo/lustre-discuss