[Lustre-discuss] Slow Tar File Extraction

[Mike Hanby]

Howdy,

Lustre 1.8.5 (CentOS 5.5 x86_64 using Lustre provided RPMs)
3 x OSS each serving 2 OSTs
1 x MDS

Client machine is connected via Infiniband to the Lustre filesystem

One of our users reported that their tar files are taking abnormally long to extract on the Lustre file system (25 minutes), yet on their NFS mounted home the extraction takes approximately 10 seconds.

I've duplicated the issue using their tar file. It's not compressed, is 126MB in size and contains 9000 files in a single subdirectory, most of the files in the tar file are 20K or less in size.

Here are the results:
* Extraction
  * NFS home: 10 seconds
  * Lustre scratch: 20 minutes
* md5sum for all 9000 files
  * NFS home: 7 seconds
  * Lustre scratch: 6 minutes

The command "ls -l" in the directory on both Lustre and NFS home return with similar speed.

I've run the same test extraction on several different clients with the same results. I've also setstripe to 1 on the extraction directory without any change.

Anyone have any suggestions or ideas?

Thanks, Mike