bugGluster - Bugs: bug #17280, XLATOR - getattr prefetch

 
 

bug #17280: XLATOR - getattr prefetch

Submitter:  Anand Avati <avati>
Submitted:  Thu 03 Aug 2006 02:47:23 PM UTC
   
 
Category:  GlusterFS Severity:  4 - Important
Priority:  5 - Normal Item Group:  Improper behaviour
Status:  Fixed Privacy:  Public
Assigned to:  gowda Originator Name:  *
Open/Closed:  Closed Release: 
Operating System:  GNU/Linux Reproducibility:  None
* Mandatory Fields

Add a New Comment Rich Markup
   

Thu 14 Sep 2006 01:59:15 PM UTC, comment #5: 

NOTE - flush the cache held whenever any entry in the cache undergoes a change (chmod, unlink, chown) or if a new file is created in the directory (open, mknod, symlink, link, rename)

Anand Avati <avati>
Group Member
Thu 14 Sep 2006 01:57:30 PM UTC, comment #4: 

publish performance figures with and without stat-prefetch translator for the combinations of cases -

1. large timeout for cache
2. small timeout for cache
3. directories with large entries
4. directories with small number of entries
5. parallel ls -R


also inspect if performance can be improved by internal restructuring of data structures.

check for thread safety.

Anand Avati <avati>
Group Member
Sun 06 Aug 2006 10:47:33 PM UTC, comment #3: 
  • getattr xlator implementation with prefetching using getattr for individual entries in directory is not giving any performance improvement as the number of network calls is still the same.
Basavanagowda Kanur <gowda>
Group Member
Sat 05 Aug 2006 10:32:40 AM UTC, comment #2: 

to confirm on the previous comment, i observed that network throughput during the 'ls -l' is just 60kbit/sec. Clearly there is a need to perform 'bulk' operation as said before to exploit network i/o.

Anand Avati <avati>
Group Member
Sat 05 Aug 2006 10:29:20 AM UTC, comment #1: 

the current getattr xlator is not giving the expected performance boost.

i observed that multiple getattr calls over the network is actually slowing the process.

need to enhance readdir to embed each entry's stat along with the entry and that should be cached for future getattr calls. Calling multiple getattr within readdir is not solving. One network transaction should get all entries and their stat() in one shot.

Anand Avati <avati>
Group Member
Thu 03 Aug 2006 02:47:23 PM UTC, original submission:  

getattr prefetching should be done preferably when a readdir() is done expecting that getattr will be performed on those entries next

Anand Avati <avati>
Group Member

 

(Note: upload size limit is set to 16384 kB, after insertion of the required escape characters.)

Attach Files:
   
   
Comment:
   

No files currently attached

 

Depends on the following items: None found

Items that depend on this one: None found

 

Carbon-Copy List
  • -email is unavailable- added by avati (Updated the item)
  •  

    There are 0 votes so far. Votes easily highlight which items people would like to see resolved in priority, independently of the priority of the item set by tracker managers.

    Only logged-in users can vote.

     

    Follow 10 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    2007-05-06 avati StatusIn Progress Fixed
        Open/ClosedOpen Closed
    2006-08-05 avati StatusFixed In Progress
    2006-08-05 avati Item GroupMissing Feature Improper behaviour
        Open/ClosedClosed Open
    2006-08-04 gowda StatusIn Progress Fixed
        Open/ClosedOpen Closed
    2006-08-03 avati Severity3 - Normal 4 - Important
        StatusNone In Progress
        Assigned toNone gowda

    Back to the top

    Powered by Savane 3.13-3230.
    Corresponding source code