hbase-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Stack <st...@duboce.net>
Subject Re: What is the best way to return scanner stats to client from co-processor?
Date Mon, 29 Oct 2018 18:05:14 GMT
On Wed, Oct 24, 2018 at 5:29 PM Alex Baranau <alex.baranov.v@gmail.com>
wrote:

> Hi,
>
> I'd like to return some scanner statistics from co-processor back to the
> client. E.g. number of rows filtered out. There isn't a way to add
> an arbitrary attributes to Result object, which would be simplest--e.g. I
> could do that in postScannerNext.
>
> The only way I can think of, is to add special Result object--again
> in postScannerNext--to the result set. The Result object would carry the
> needed info as bytes and could be watched for and interpreted on the client
> side. Is it reasonable at all? Is it at all dangerous to do that in
> postScannerNext or in general? Would it interfere with some client or
> server-side logic?
>
> Any ideas are welcome!
>
> Thank you in advance,
> Alex Baranau
>


Hey Alex:

Does the ScanMetrics feature help at all in your case (See
AbstractClientScanner#getScanMetrics()).

On the Result, yeah, it is intentionally dumb -- a package of Cells. A
'speical' Result appended by the CP seems like a good way to go though....
Would be interested if you make progress sir.

S

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message