[gpfsug-discuss] Biggest file that will fit inside an inode?

[Simon Thompson (Research Computing - IT Services)]

Would you tier an in-inode file to the cloud?

I mean, I wouldn't tier an in-inode file out to tape?

Simon
________________________________________
From: gpfsug-discuss-bounces at spectrumscale.org [gpfsug-discuss-bounces at spectrumscale.org] on behalf of Oesterlin, Robert [Robert.Oesterlin at nuance.com]
Sent: 03 October 2016 16:56
To: gpfsug main discussion list
Subject: Re: [gpfsug-discuss] Biggest file that will fit inside an inode?

What's going be taken away if you use Encryption or Transparent Cloud Tiering?


Bob Oesterlin
Sr Storage Engineer, Nuance HPC Grid


From: <gpfsug-discuss-bounces at spectrumscale.org> on behalf of Marc A Kaplan <makaplan at us.ibm.com>
Reply-To: gpfsug main discussion list <gpfsug-discuss at spectrumscale.org>
Date: Monday, October 3, 2016 at 10:46 AM
To: gpfsug main discussion list <gpfsug-discuss at spectrumscale.org>
Subject: [EXTERNAL] Re: [gpfsug-discuss] Biggest file that will fit inside an inode? 3968!!

On a non-SELINUX system the answer is 3968 of data in a 4K inode, just 128 bytes of metadata.

Caution: it's possible in some future release, this could change ... I don't know of any plans, I'm just saying ...

Inode 16346892 [16346892] snap 0 (index 12 in block 255420):
  Inode address: 6:123049056 size 4096 nAddrs 330
  indirectionLevel=INODE status=USERFILE
  objectVersion=1 generation=0xC0156CB nlink=1
  owner uid=0 gid=0 mode=0200100644: -rw-r--r--
  blocksize code=5 (32 subblocks)
  lastBlockSubblocks=0
  checksum=0xAD8E0B4B is Valid
  fileSize=3968 nFullBlocks=0
  currentMetadataReplicas=1 maxMetadataReplicas=2
  currentDataReplicas=1 maxDataReplicas=2
  ...
  Data [3968]:
0000000000000000: BCA91252 2B64BEDC A7D7BA9D D5BE8C30  *...R+d.........0*
...
0000000000000F70: DA925E2F 16A68C01 03CA5E37 08D72B7F  *..^/......^7..+.*
  trailer: is NULL