Project

General

Profile

Bug #4752

fan out read zio taskqs

Added by Christopher Siden over 5 years ago. Updated over 5 years ago.

Status:
Closed
Priority:
Normal
Category:
zfs - Zettabyte File System
Start date:
2014-04-14
Due date:
% Done:

100%

Estimated time:
Difficulty:
Medium
Tags:
needs-triage

Description

Analysis by Adam Leventhal:

Seeing lock contention on the read taskq:

Count indv cuml rcnt     nsec Lock                   Caller                  
609570   4%   9% 0.00     8695 0xffffff04f07a8d90     taskq_thread+0x2fe      

      nsec ------ Time Distribution ------ count     Stack                   
       256 |                               4270      thread_start+0x8        
       512 |@@@                            74043     
      1024 |@@@                            75172     
      2048 |@@@@                           91767     
      4096 |@@@@@@                         132984    
      8192 |@@@@@                          107390    
     16384 |@@                             54033     
     32768 |@                              31946     
     65536 |@                              24390     
    131072 |                               12785     
    262144 |                               586       
    524288 |                               15        
   1048576 |                               1         
   2097152 |                               177       
   4194304 |                               11        
-------------------------------------------------------------------------------
Count indv cuml rcnt     nsec Lock                   Caller                  
493225   3%  13% 0.00     7513 0xffffff04f07a8d90     taskq_dispatch_ent+0x51 

      nsec ------ Time Distribution ------ count     Stack                   
       256 |                               14430    
spa_taskq_dispatch_ent+0x80
       512 |@@                             39491     zio_taskq_dispatch+0x78 
      1024 |@                              24552     zio_interrupt+0x18      
      2048 |@                              32451     vdev_disk_io_intr+0x4f  
      4096 |@@@@@@@@@@                     172179    biodone+0x35            
      8192 |@@@@@@                         112444    sd_buf_iodone+0x65      
     16384 |@@@                            53604    
sd_mapblockaddr_iodone+0x45
     32768 |@                              23587     sd_return_command+0x12a 
     65536 |                               14515     sdintr+0x3ac            
    131072 |                               5643      scsi_hba_pkt_comp+0x63  
    262144 |                               258       mpt_doneq_thread+0x8e   
    524288 |                               10        thread_start+0x8        
   1048576 |                               2         
   2097152 |                               56        
   4194304 |                               2         
   8388608 |                               1

History

#1

Updated by Electric Monk over 5 years ago

git commit 1b497ab83e8f1c58bba5da59c649207a442a4720

Author: Adam H. Leventhal <ahl@delphix.com>

4752 fan out read zio taskqs
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Matthew Ahrens <mahrens@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: Eric Schrock <eric.schrock@delphix.com>
Reviewed by: Dan McDonald <danmcd@omniti.com>
Approved by: Dan McDonald <danmcd@omniti.com>

#2

Updated by Christopher Siden over 5 years ago

  • Status changed from In Progress to Closed
commit 1b497ab83e8f1c58bba5da59c649207a442a4720
Author: Adam H. Leventhal <ahl@delphix.com>
Date:   Tue Apr 15 20:44:44 2014

    4752 fan out read zio taskqs
    Reviewed by: George Wilson <george.wilson@delphix.com>
    Reviewed by: Matthew Ahrens <mahrens@delphix.com>
    Reviewed by: Christopher Siden <christopher.siden@delphix.com>
    Reviewed by: Eric Schrock <eric.schrock@delphix.com>
    Reviewed by: Dan McDonald <danmcd@omniti.com>
    Approved by: Dan McDonald <danmcd@omniti.com>

Also available in: Atom PDF