phpBB2Refugees.com Logo
Not affiliated with or endorsed by the phpBB Group

Register •  Login 

Continue the legacy...

Welcome to all phpBB2 Refugees!Wave Smilie

This site is intended to continue support for the legacy 2.x line of the phpBB2 bulletin board package. If you are a fan of phpBB2, please, by all means register, post, and help us out by offering your suggestions. We are primarily a community and support network. Our secondary goal is to provide a phpBB2 MOD Author and Styles area.

MyISAM or Heap (MEMORY)


 
Search this topic... | Search phpBB2 Discussion... | Search Box
Register or Login to Post    Index » phpBB2 Discussion  Previous TopicPrint TopicNext Topic
Author Message
Jim_UK
Board Member



Joined: 19 Nov 2008

Posts: 538
Location: North West UK


flag
PostPosted: Sat Jan 03, 2009 8:54 pm 
Post subject: MyISAM or Heap (MEMORY)

I have just been looking at the Database Maintenance Mod and on first accessing it saw that there was a link to select converting the table phpbb_sessions to a Heap table from a MyISAM.
I made the change (On a test board on localhost) and the link has now vanished. The suggestion was that selecting Heap instead of MyISAM for that table would speed the board up.
Can anyone offer a suggestion as to why it should and would any difference really make it worth making that change. Mine is a relatively low traffic site with rarely more than about 10 folks on at a time.

Jim
Back to top
Dog Cow
Board Member



Joined: 18 Nov 2008

Posts: 378


flag
PostPosted: Sat Jan 03, 2009 10:00 pm 
Post subject: Re: MyISAM or Heap (MEMORY)

It will save disk activity as the table data is stored in RAM, while the structure is saved on the HD. Whenever mysqld restarts, the table data is lost.

Some web hosts have put a limit on the number of rows allowed in a memory table. There's a way to increase it, but not all hosts allow that since they typically have one mysql server serving 100 or so databases.

In any case, you can do whatever you want, it's just that if you start getting several hundred sessions, you may run into the problem I just mentioned.
Back to top
Ptirhiik
Board Member



Joined: 19 Nov 2008

Posts: 114


flag
PostPosted: Sat Jan 03, 2009 11:18 pm 
Post subject: Re: MyISAM or Heap (MEMORY)

Bad idea indeed: mySQL servers are perfectly able to handle myISAM (or innoDB) tables very oftently updated a smart way: no need to force it to work into memory, what will push the system to generate cached files a worth way than mySQL server does. Heap has to be reserved for small, static tables like parameters ones that never change, this for large system (potentially clustered). On small system (eg same server for mySQL server and Apache), this will only result to an extra memory consumption, what will rather slow down the whole things as soon as the memory will reach its true limits.
Back to top
espicom
Board Member



Joined: 24 Nov 2008

Posts: 55
Location: Woodstock, IL


flag
PostPosted: Sun Jan 04, 2009 12:21 am 
Post subject: Re: MyISAM or Heap (MEMORY)

If the MySQL server is running version 4.0.x or later, converting back to Heap shouldn't be offered. It was an advantage on 3.x, even with the limit on the maximum table size, but it is of no advantage on 4.x+.
Back to top
Jim_UK
Board Member



Joined: 19 Nov 2008

Posts: 538
Location: North West UK


flag
PostPosted: Sun Jan 04, 2009 3:18 pm 
Post subject: Re: MyISAM or Heap (MEMORY)

Thanks for the info guys. I shall leave the table at MyISAM then.

Jim
Back to top
Display posts from previous:   
Register or Login to Post    Index » phpBB2 Discussion  Previous TopicPrint TopicNext Topic
Page 1 of 1 All times are GMT
 
Jump to:  

Index • About • FAQ • Rules • Privacy • Search •  Register •  Login 
Not affiliated with or endorsed by the phpBB Group
Powered by phpBB2 © phpBB Group
Generated in 0.0170 seconds using 15 queries. (SQL 0.0022 Parse 0.0005 Other 0.0142)
phpBB Customizations by the phpBBDoctor.com
Template Design by DeLFlo and MomentsOfLight.com Moments of Light Logo