It sounds as though you could be having troubles with Garbage Collection. Check
your cassandra system logs and search for "GC". If you see frequent garbage
collections taking more than a second or two to complete, you're going to need
to do some configuration tweaking.
On 05/07/2015 04:44 AM, Pierre Devops wrote:
Hi,
I m streaming a big sstable using bulk loader of sstableloader but it's very
slow (3 Mbytes/sec) :
Summary statistics:
Connections per host: : 1
Total files transferred: : 1
Total bytes transferred: : 10357947484
Total duration (ms): : 3280229
Average transfer rate (MB/s): : 3
Peak transfer rate (MB/s): : 3
I'm on a single node configuration, empty keyspace and table, with good hardware
8x2.8ghz 32G RAM, dedicated to cassandra, so it's plenty of ressource for the
process. I'm uploading from another server.
The sstable is 9GB in size and have 4 partitions, but a lot of rows per
partition (like 100 millions), the clustering key is a INT and have 4 other
regulars columns, so approximatly 500 millions cells per ColumnFamily.
When I upload I notice one core of the cassandra node is full CPU (all other
cores are idleing), so I assume I'm CPU bound on node side. But why ? What the
node is doing ? Why does it take so long time ?
--
Mike Neir
Liquid Web, Inc.
Infrastructure Administrator
