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From Mark Jones <>
Subject RE: What's the best maximum size for a single column?
Date Thu, 29 Apr 2010 15:38:20 GMT
The max size would probably be best determined by looking at the size of your MemTable

   ~ Flush memtable after this much data has been inserted, including
   ~ overwritten data.  There is one memtable per column family, and
   ~ this threshold is based solely on the amount of data stored, not
   ~ actual heap memory usage (there is some overhead in indexing the
   ~ columns).

Read repair is on a per column basis, every column gets a timestamp, and the overhead of a
name.  So, balance those 3 out and you have a pretty good idea of what to do.

From: Dop Sun []
Sent: Thursday, April 29, 2010 7:38 AM
Subject: RE: What's the best maximum size for a single column?

Is there any practical number can refer to?

Like what's the size (big one) used in single columns in your application?

From: uncle mantis []
Sent: Thursday, April 29, 2010 1:57 AM
Subject: Re: What's the best maximum size for a single column?

There is no column size limitation. As to performance due to the size of a column and with
the speeds that Cassandra are running at, I don't belive it would make a bit of a difference
if it was 1 byte or a million bytes.

Can anyone here prove me right or wrong?


On Wed, Apr 28, 2010 at 7:37 AM, Dop Sun <<>>

Yesterday, I saw a lot of discussion about how to store a file (big one). It looks like the
suggestion is store in multiple rows (even not multiple column in a single row).

My question is:
Is there any best maximum column size which can help to make the decision on the segment size?
Is this related with the memory size or other stuff?


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