Metadata locking in MySQL 5.5
Upcoming SlideShare
Loading in...5
×
 

Metadata locking in MySQL 5.5

on

  • 3,173 views

User Conference 2011 presentation

User Conference 2011 presentation

Statistics

Views

Total Views
3,173
Views on SlideShare
3,083
Embed Views
90

Actions

Likes
0
Downloads
22
Comments
0

2 Embeds 90

http://lj-toys.com 82
http://l.lj-toys.com 8

Accessibility

Categories

Upload Details

Uploaded via as Adobe PDF

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

Metadata locking in MySQL 5.5 Metadata locking in MySQL 5.5 Presentation Transcript

  • Metadata locking in MySQL 5.5 Konstantin Osipov Engineer @ Mail.Rukostja.osipov@gmail.com These slides released under the Creative Commons  Attribution­Noncommercial­Share Alike License
  • Mastering a 25-foot saw
  • DDL vs. DML: an illustration
  • What if... a transactional catalog
  • Locking agents
  • Define the problem (2)Four groups of bugs:- ALTER, DROP violate ACID- … or ... break replication- deadlocks in LOCK TABLES, FLUSH, SET GLOBAL read_only and ALTER- DML doesnt scale or THANK YOU LOCK_open
  • Define the problem (3)
  • In come metadata locks
  • Deadlock detectionHow does a typical wait-for grpah look like?
  • How to plug inEngines need to plug-in to avoid cross-storage-engine deadlocks.- its safe to #include “mdl.h”, no extra deps- subclass MDL_waitfor_subgraph to accept- MDL_waitfor_graph_visitor- let us know when youre waiting, by calilng- MDL_context::will_wait_for()
  • Performance impact
  • The roadmap - help us add cross-storage-engine deadlockdetection!- thr_lock.c and handler::store_lock() need not bemandatory any more- consistent DDL across all NDB cluster- shard MDL_set (performance++)- instrumentation
  • Performance impact
  • Thats it. Thank you for coming! Further reading: WL#3873, WL#3726, WL#4284 Mdl.pdf is available in MySQL internals manual.