You are viewing a plain text version of this content. The canonical link for it is here.
Posted to user@ignite.apache.org by woo charles <ig...@gmail.com> on 2017/04/03 06:54:50 UTC
CPU Usage on distributed queries
Hi,
I have conducted a test on distributed query performance.
I have created 5 server nodes(java) in 3 different server.
40000 records are entered.
I created 80 Threads and each thread looped following sql 100 times.
select * from user where age<18
(about 50 records is selected)
*** age is not key / index
After all, I have found that the CPU usage of 2 server nodes (the oldest
and the second oldest) jump to a significantly high level (from 5% to
80%-90%) where other 3 nodes increase from 5% to 18% only.
Why this happens?
Re: CPU Usage on distributed queries
Posted by Alexander Fedotov <al...@gmail.com>.
Hi,
Do the two nodes with the highest load reside on the same physical machine?
If that is so and the queries were run from that machine, then I could
assume that the cpu load is due to the reduce step being held there.
Kind regards,
Alex
3 апр. 2017 г. 8:45 PM пользователь "vdpyatkov" <vl...@gmail.com>
написал:
Hi,
How was Ignite nodes and physical machines mapped?
Where Ignite nodes more there is CPU utilization greater, isn't it?
Where were SQL query generated (on one of a srever node or other)?
I think, CPU utilization shuold be same over of nodes, because SQL executed
as Map Reduce task.
--
View this message in context: http://apache-ignite-users.
70518.x6.nabble.com/CPU-Usage-on-distributed-queries-tp11652p11680.html
Sent from the Apache Ignite Users mailing list archive at Nabble.com.
Re: CPU Usage on distributed queries
Posted by vdpyatkov <vl...@gmail.com>.
Hi,
How was Ignite nodes and physical machines mapped?
Where Ignite nodes more there is CPU utilization greater, isn't it?
Where were SQL query generated (on one of a srever node or other)?
I think, CPU utilization shuold be same over of nodes, because SQL executed
as Map Reduce task.
--
View this message in context: http://apache-ignite-users.70518.x6.nabble.com/CPU-Usage-on-distributed-queries-tp11652p11680.html
Sent from the Apache Ignite Users mailing list archive at Nabble.com.