[
https://issues.apache.org/jira/browse/HADOOP-18190?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Daniel Carl Jones updated HADOOP-18190:
---------------------------------------
Description:
There is a lot more happening in reads, so there's a lot more data to collect
and publish in IO stats for us to view in a summary at the end of processes as
well as get from the stream while it is active.
Some useful ones would seem to be:
counters
* is in memory. using 0 or 1 here lets aggregation reports count total #of
memory cached files.
* prefetching operations executed
* errors during prefetching
gauges
* number of blocks in cache
* total size of blocks
* active prefetches
+ active memory used
duration tracking count/min/max/ave
* time to fetch a block
* time queued before the actual fetch begins
* time a reader is blocked waiting for a block fetch to complete
and some info on cache use itself
* number of blocks discarded unread
* number of prefetched blocks later used
* number of backward seeks to a prefetched block
* number of forward seeks to a prefetched block
the key ones I care about are
# memory consumption
# can we determine if cache is working (reads with cache hit) and when it is
not (misses, wasted prefetches)
# time blocked on executors
The stats need to be accessible on a stream even when closed, and aggregated
into the FS. once we get per-thread stats contexts we can publish there too and
collect in worker threads for reporting in task commits
was:
There is a lot more happening in reads, so lot of more to collect and publish
in IO stats for us to view in a summary at the end of processes as well as get
from the stream while it is active
Some useful ones would seem to be
counters
* is in memory. using 0 or 1 here lets aggregation reports count total #of
memory cached files.
* prefetching operations executed
* errors during prefetching
gauges
* number of blocks in cache
* total size of blocks
* active prefetches
+ active memory used
duration tracking count/min/max/ave
* time to fetch a block
* time queued before the actual fetch begins
* time a reader is blocked waiting for a block fetch to complete
and some info on cache use itself
* number of blocks discarded unread
* number of prefetched blocks later used
* number of backward seeks to a prefetched block
* number of forward seeks to a prefetched block
the key ones I care about are
# memory consumption
# can we determine if cache is working (reads with cache hit) and when it is
not (misses, wasted prefetches)
# time blocked on executors
The stats need to be accessible on a stream even when closed, and aggregated
into the FS. once we get per-thread stats contexts we can publish there too and
collect in worker threads for reporting in task commits
> s3a prefetching streams to collect iostats on prefetching operations
> --------------------------------------------------------------------
>
> Key: HADOOP-18190
> URL: https://issues.apache.org/jira/browse/HADOOP-18190
> Project: Hadoop Common
> Issue Type: Sub-task
> Components: fs/s3
> Affects Versions: 3.4.0
> Reporter: Steve Loughran
> Priority: Major
>
> There is a lot more happening in reads, so there's a lot more data to collect
> and publish in IO stats for us to view in a summary at the end of processes
> as well as get from the stream while it is active.
> Some useful ones would seem to be:
> counters
> * is in memory. using 0 or 1 here lets aggregation reports count total #of
> memory cached files.
> * prefetching operations executed
> * errors during prefetching
> gauges
> * number of blocks in cache
> * total size of blocks
> * active prefetches
> + active memory used
> duration tracking count/min/max/ave
> * time to fetch a block
> * time queued before the actual fetch begins
> * time a reader is blocked waiting for a block fetch to complete
> and some info on cache use itself
> * number of blocks discarded unread
> * number of prefetched blocks later used
> * number of backward seeks to a prefetched block
> * number of forward seeks to a prefetched block
> the key ones I care about are
> # memory consumption
> # can we determine if cache is working (reads with cache hit) and when it is
> not (misses, wasted prefetches)
> # time blocked on executors
> The stats need to be accessible on a stream even when closed, and aggregated
> into the FS. once we get per-thread stats contexts we can publish there too
> and collect in worker threads for reporting in task commits
--
This message was sent by Atlassian Jira
(v8.20.7#820007)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
