From: Brian Acton <ac...@whatsapp.com>
Date: Fri, 2 Apr 2010 11:22:52 -0700
Local: Fri, Apr 2 2010 2:22 pm
Subject: Re: [erlang-questions] Mnesia deadlock with large volume of dirty operations?
I'm sorry. I neglected to tell you what I had done on the previous day. On the previous day, I had attempted to delete some old records using this mnesia:write_lock_table(offline_msg), This delete finished on the 1st node but subsequently locked up all the So to recap, on day 1 - transaction start, table lock, delete objects - finished in about In both cases, the cluster blew up and became unusable for at least 20-30 Should I try day 3 - transaction start, no table lock, delete objects ? is the table lock too coarse grained ? considering that the cluster has --b > On Fri, Apr 2, 2010 at 10:19 AM, Dan Gudmundsson <d...@erlang.org> wrote: > > What you get is an overloaded mnesia_tm (very long msg queues), > > So transactions will be blocked waiting on mnesia_tm to process those > > /Dan > > On Fri, Apr 2, 2010 at 1:11 AM, Brian Acton <ac...@whatsapp.com> wrote: > >> I am running R13B04 SMP on FreeBSD 7.3. I have a cluster of 7 nodes > >> I have a table of 1196143 records using about 1.504GB of storage. It's a > >> I decided that since there was a 2GB limit in mnesia that I should do > >> Trying to avoid major problems with Mnesia, transaction load, and > >> I started slow, deleting first 10, then 100, then 1000, then 10000, then > >> The first five deletions went through nicely and caused minimal to no > >> Unfortunately, the very last delete blew up the system. My delete > >> Does anyone have any clues on what went wrong? I am attaching my code > >> --b > >> Mnesia configuration tunables: > >> -mnesia no_table_loaders 20 > >> Example error message: > >> ** WARNING ** Mnesia is overloaded: {mnesia_tm, message_queue_len, > >> Sample code: > >> Select = fun(Days) -> > >> Count = fun(Days) -> length(Select(Days)) end. > >> Delete = fun(Days, Total) -> > > ________________________________________________________________ You must Sign in before you can post messages.
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