[erlang-questions] How many fragments would be proper for 1milions records in mensia?
Mon Jul 28 12:28:03 CEST 2008
2008/7/28, Valentin Micic <>:
> I'd say that also depends on what storage method you're using. Thus, in a
> case you're planning to use DETS (disc_only_copy), you may want to consider
> fragmentation even for 1 million... In my experience, the performance
> deteriorates(*) when table gets populated beyond, say, 250,000 entries (if
> entries are reasonably complex terms).
Oh,that will be a problem.Can I say mnesia is not proper for very large
If I keep every fragment 250,000 records, then 100 million records will be
400 fragments,is it a problem for mnesia?
What's the size of your largest mnesia table in your application ?
> In addition, if you increase a number of dets fragments, make sure that you
> also increase a number of I/O threads (+A) to some reasonable value(**).
> (*) Inserts and/or updates are affected, read seems to keep good
> performance levels.
> (**) If you are using 32-bit environment, try not to get carried away with
> a number of I/O threads, as the cost in memory may be substantial.
> ----- Original Message ----- From: "Ulf Wiger" <>
> To: "devdoer bird" <>; <>
> Sent: Sunday, July 27, 2008 10:12 AM
> Subject: Re: [erlang-questions] How many fragments would be proper for
> 1milions records in mensia?
> Depending on object size, you may well have just a single
>> table/fragment. 1 million objects is not that much.
>> Ulf W
>> 2008/7/27, devdoer bird <>:
>>> Considering the access performance , easy mangement ,how many fragments
>>> would be proper for 1 milions records in mensia? Are there any rules
>>> the number of fragments and the number of total records?
>> erlang-questions mailing list
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