ZhangYao has posted comments on this change. ( 
http://gerrit.cloudera.org:8080/13975 )

Change subject: KUDU-2911: Consider the available space when selecting data 
dirs for tablets
......................................................................


Patch Set 4:

(2 comments)

http://gerrit.cloudera.org:8080/#/c/13975/3/src/kudu/fs/data_dirs.h
File src/kudu/fs/data_dirs.h:

http://gerrit.cloudera.org:8080/#/c/13975/3/src/kudu/fs/data_dirs.h@470
PS3, Line 470: vailable disk space of directory.
             :   // The resulting behavior f
> How will this behave during the creation of a very large table, or at the s
Here is more complex if tablet were created but only start filling up. Under 
that condition, disk space will not change so althought
PO2C may not let all tablet select the same directory but it still have risk to 
make one directory handle too much tablets.
If use the (available space) / (tablets count):
1?When create tablets with data writing soon. It works like just use available 
space with the assumption that all tablets with same size.It do not need to 
assume that the disks are same size.
2?When create a lot of tablets once. It can prevent selecting the same 
directory which more available space.


http://gerrit.cloudera.org:8080/#/c/13975/3/src/kudu/fs/data_dirs.cc
File src/kudu/fs/data_dirs.cc:

http://gerrit.cloudera.org:8080/#/c/13975/3/src/kudu/fs/data_dirs.cc@988
PS3, Line 988:     int uuid_idx = (*group_uuid_indices)[i];
> It looks like PS4 works like this:
Yeah, this patch I just simply revert the code, I will update later.
It can use PO2C to randomly select two directory and then choose the one with 
more available space.
And the strategy here is not that complex because when we create block we will 
write data.



--
To view, visit http://gerrit.cloudera.org:8080/13975
To unsubscribe, visit http://gerrit.cloudera.org:8080/settings

Gerrit-Project: kudu
Gerrit-Branch: master
Gerrit-MessageType: comment
Gerrit-Change-Id: I194c4965ee64aed728e3b84e684c04d445cbe529
Gerrit-Change-Number: 13975
Gerrit-PatchSet: 4
Gerrit-Owner: ZhangYao <[email protected]>
Gerrit-Reviewer: Adar Dembo <[email protected]>
Gerrit-Reviewer: Andrew Wong <[email protected]>
Gerrit-Reviewer: Kudu Jenkins (120)
Gerrit-Reviewer: Yingchun Lai <[email protected]>
Gerrit-Reviewer: ZhangYao <[email protected]>
Gerrit-Comment-Date: Fri, 02 Aug 2019 06:40:15 +0000
Gerrit-HasComments: Yes

Reply via email to