> As per datastax documentation, a manual compaction forces the admin to start > compaction manually and disables the automated compaction (atleast for major > compactions but not minor compactions ) It does not disable compaction. it creates one big file, which will not be compacted until there are (by default) 3 other very big files.
> 1. Does a nodetool stop compaction also force the admin to manually run major > compaction ( I.e. disable automated major compactions ? ) No. Stop just stops the current compaction. Nothing is disabled. > 2. Can a node restart reset the automated major compaction if a node gets > into a manual mode compaction for whatever reason ? Major compaction is not automatic. It is the manual nodetool compact command. Automatic (minor) compaction is controlled by min_compaction_threshold and max_compaction_threshold (for the default compaction strategy). > 3. What is the ideal number of SSTables for a table in a keyspace ( I mean > are there any indicators as to whether my compaction is alright or not ? ) This is not something you have to worry about. Unless you are seeing 1,000's of files using the default compaction. > For example, I have seen SSTables on the disk more than 10 days old wherein > there were other SSTables belonging to the same table but much younger than > the older SSTables ( No problems. > 4. Does a upgradesstables fix any compaction issues ? What are the compaction issues you are having ? Cheers ----------------- Aaron Morton Freelance Cassandra Developer New Zealand @aaronmorton http://www.thelastpickle.com On 18/11/2012, at 1:18 AM, Ananth Gundabattula <agundabatt...@gmail.com> wrote: > > We have a cluster running cassandra 1.1.4. On this cluster, > > 1. We had to move the nodes around a bit when we were adding new nodes > (there was quite a good amount of node movement ) > > 2. We had to stop compactions during some of the days to save some disk > space on some of the nodes when they were running very very low on disk > spaces. (via nodetool stop COMPACTION) > > > As per datastax documentation, a manual compaction forces the admin to start > compaction manually and disables the automated compaction (atleast for major > compactions but not minor compactions ) > > > Here are the questions I have regarding compaction: > > 1. Does a nodetool stop compaction also force the admin to manually run major > compaction ( I.e. disable automated major compactions ? ) > > 2. Can a node restart reset the automated major compaction if a node gets > into a manual mode compaction for whatever reason ? > > 3. What is the ideal number of SSTables for a table in a keyspace ( I mean > are there any indicators as to whether my compaction is alright or not ? ) . > For example, I have seen SSTables on the disk more than 10 days old wherein > there were other SSTables belonging to the same table but much younger than > the older SSTables ( The node movement and repair and cleanup happened > between the older SSTables and the new SSTables being touched/modified) > > 4. Does a upgradesstables fix any compaction issues ? > > Regards, > Ananth
