[
https://issues.apache.org/jira/browse/HDFS-7331?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14220285#comment-14220285
]
Aaron T. Myers commented on HDFS-7331:
--------------------------------------
bq. I know most of the metric systems will collect metrics and plot graphs
directly. I'm unaware of any metrics systems that can do subtraction
out-of-the-box. Some pointers are appreciated.
Ganglia (and I bet basically all monitoring software) can do this out of the
box. In Ganglia, one need only specify the slope of the metric to be a counter
instead of a gauge, in which case the default is to store the values as a
per-second rate. In general counters are strictly better than calculating the
rate on the producer side, since the monitoring software can derive the latter
from the former, but not the reverse. Also, the monitoring sampling frequency
matters much less if you use a counter because if you calculate the rate on the
producer side, then it's entirely possible that if your monitoring software's
sample frequency is too low then one can miss anomalies in the values and have
no way to detect this.
> Add Datanode network counts to datanode jmx page
> ------------------------------------------------
>
> Key: HDFS-7331
> URL: https://issues.apache.org/jira/browse/HDFS-7331
> Project: Hadoop HDFS
> Issue Type: Improvement
> Components: datanode
> Reporter: Charles Lamb
> Assignee: Charles Lamb
> Priority: Minor
> Attachments: HDFS-7331.001.patch, HDFS-7331.002.patch,
> HDFS-7331.003.patch, HDFS-7331.004.patch
>
>
> Add per-datanode counts to the datanode jmx page. For example, networkErrors
> could be exposed like this:
> {noformat}
> }, {
> ...
> "DatanodeNetworkCounts" : "{\"dn1\":{\"networkErrors\":1}}",
> ...
> "NamenodeAddresses" :
> "{\"localhost\":\"BP-1103235125-127.0.0.1-1415057084497\"}",
> "VolumeInfo" :
> "{\"/tmp/hadoop-cwl/dfs/data/current\":{\"freeSpace\":3092725760,\"usedSpace\":28672,\"reservedSpace\":0}}",
> "ClusterId" : "CID-4b38f2ae-5e58-4e15-b3cf-3ba3f46e724e"
> }, {
> {noformat}
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
