See swappiness: http://en.wikipedia.org/wiki/Swappiness
$ cat /proc/sys/vm/swappiness
# echo 20 > /proc/sys/vm/swappiness
tl;dr Having a "large" value for swappiness might cause the operating system to move your
process to "swap" instead of main memory which would likely cause it to lose its
ZooKeeper locks and die. The larger the value, the more aggressive the OS is in putting things to
swap, the lower the value, the less so. It's not recommended to ever disable swap completely though.
Wyatt Frelot wrote:
I have been looking in the logs and I found something…just not sure
about it’s impact:
2015-02-02 22:21:04,390 [server.Accumulo] WARN : System swappiness
setting is greater than ten (60) which can cause time-sensitive
operations to be delayed. Accumulo is time sensitive because it needs
to maintain distributed lock agreement.
Would this cause it?
Wyatt
On Feb 2, 2015, at 17:03, John Vines <[email protected]
<mailto:[email protected]>> wrote:
I'm sorry, I meant nmode:2181 in your actual code.
On Mon, Feb 2, 2015 at 4:53 PM, Wyatt Frelot
<[email protected]
<mailto:[email protected]>> wrote:
John,
I think I did it right. Here is what I get when I run it the way
that you suggested.
vagrant@mnode:/cloud/accumulo/lib$ nc mnode:2181
This is nc from the netcat-openbsd package. An alternative nc is
available
in the netcat-traditional package.
usage: nc [-46bCDdhjklnrStUuvZz] [-I length] [-i interval] [-O
length]
[-P proxy_username] [-p source_port] [-q seconds] [-s source]
[-T toskeyword] [-V rtable] [-w timeout] [-X proxy_protocol]
[-x proxy_address[:port]] [destination] [port]
On Feb 2, 2015, at 16:38, John Vines <[email protected]
<mailto:[email protected]>> wrote:
It looks like you're declaring your ZK connect string as
"mnode". What happens if you do "mnode:2181"?
On Mon, Feb 2, 2015 at 4:17 PM, Wyatt Frelot
<[email protected]
<mailto:[email protected]>> wrote:
Mike
If I am reading this correctly, it appears as if everything
is in order:
vagrant@mnode:/vagrant$ nc mnode 2181
stat
Zookeeper version: 3.4.6-1569965, built on 02/20/2014 09:09 GMT
Clients:
/192.168.15.4:44488[1](queued=0,recved=84,sent=85)
/192.168.15.2:48504[0](queued=0,recved=1,sent=0)
/192.168.15.2:48262[1](queued=0,recved=1577,sent=1598)
/192.168.15.5:55540[1](queued=0,recved=434,sent=449)
/192.168.15.3:37401[1](queued=0,recved=236,sent=239)
/192.168.15.4:44480[1](queued=0,recved=244,sent=251)
/192.168.15.5:55559[1](queued=0,recved=100,sent=101)
/192.168.15.5:55564[1](queued=0,recved=88,sent=89)
Latency min/avg/max: 0/0/62
Received: 3114
Sent: 3162
Connections: 8
Outstanding: 0
Zxid: 0x71a
Mode: standalone
Node count: 270
Wyatt
On Feb 2, 2015, at 16:06, Mike Drob <[email protected]
<mailto:[email protected]>> wrote:
nc [zk-host] [zk-port]
--
Cheers
~John
