Beefy Boxes and Bandwidth Generously Provided by pair Networks
There's more than one way to do things

Re: Multiple write locking for BerkeleyDB

by samtregar (Abbot)
on Apr 23, 2008 at 20:13 UTC ( #682485=note: print w/replies, xml ) Need Help??

in reply to Multiple write locking for BerkeleyDB

How did you code your MySQL solution? What storage type did you use? I bet this will perform great, and I'm pretty sure it's guaranteed atomic for MyISAM and InnoDB (would have to check to be sure):

  UPDATE table SET counter = counter + 1 WHERE counter_id = ?;

(Assuming you have an index on counter_id of course.)

You also need to look out for the usual DB-usage traps - make sure you're caching your connection between calls, tune your configuration to make appropriate use of memory, etc.


Replies are listed 'Best First'.
Re^2: Multiple write locking for BerkeleyDB
by dino (Sexton) on Apr 23, 2008 at 20:47 UTC
    Well I used dbi and a similar syntax to the above "insert with on duplicate key update, to deal with non existing keys (in this case ips)".
    I'm a pretty inexperienced sqler so its very possible that its not optimal, but the rate was very poor (30k/min) when compared to the Berkeley alternatives.
      Try pre-loading your counters with 0s and just using UPDATE. I bet it's faster than INSERT ON DUPLICATE UPDATE. Assuming you have reasonable hardware 30k/min (500/s) seems pretty poor. But I guess it depends on how many counters there are and how many concurrent connections are trying to write at once.


        Thanks for you ip. I'm not sure I can pre load the counters with zero as I don't know what the keys will be until I read the tcpdump input. The table format is currently:
        But this is starting to get off topic and I should read up more on Mysql. (I had hoped, that there was a guide out there that talked about how to drive BerkeleyDB in full {lets do manual locking in perl}) mode and that my search fu was lacking.
      For simple things like this, using local sockets with MySQL makes a big difference. It will never be as fast as BerkeleyDB, but it should be very fast.

Log In?

What's my password?
Create A New User
Domain Nodelet?
Node Status?
node history
Node Type: note [id://682485]
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others chanting in the Monastery: (6)
As of 2023-10-04 12:17 GMT
Find Nodes?
    Voting Booth?

    No recent polls found