incubator-cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Aaron Morton <aa...@thelastpickle.com>
Subject Re: Cassandra 0.7 - Impact of row size and columns on compaction
Date Sun, 05 Dec 2010 20:35:00 GMT
AFAIK if the entire row can be read into memory the compaction will be faster. The in_memory_compaction_limit_in_mb
setting is used to decide how big the row can be before it has to use a slower two pass process. 

Also my understanding is that one of the main factors for compaction is the number of over-writes
for rows / columns. e.g. if the data for a row is spread over a lot of ss tables (for new
columns and/or updates and/or deletes) it will take longer to compact that row. 

Hope that helps. 
Aaron
 

On 04 Dec, 2010,at 09:23 AM, Narendra Sharma <narendra.sharma@gmail.com> wrote:

What is the impact (performance and I/O) of row size (in bytes) on compaction?
What is the impact (performance and I/O) of number of super columns and columns on compaction?

Does anyone has any details and data to share?

Thanks,
Naren

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
    • Unnamed multipart/related (inline, None, 0 bytes)
View raw message