New hint nc_data_move_chunk_size #203
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
When adding new data objects into an existing file, the data section may need to be moved to a higher file offset. The movement is performed in chunks. This hint allows users to customized the chunk size. The default is 1048576 bytes, i.e. 1 MiB.
wkliao
force-pushed
the
data_move_chunk
branch
from
0d82c1e to
d7cdcd4
Compare
In addition, define DRY_RUN and VERBOSE and 2 functions for debugging purpose.
wkliao
force-pushed
the
data_move_chunk
branch
from
d7cdcd4 to
d9ba4ca
Compare
Value of data_chunk depends on file striping_unit It performs best when set to striping_unit.
* use file striping unit size as moving chunk size by default. * align write offsets with the striping units to coincide the Lustre collective write file domain alignment
wkliao
force-pushed
the
data_move_chunk
branch
from
b5c59d0 to
823853a
Compare
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
When adding new data objects into an existing file, the data section may need to be moved to a higher file offset. The movement is performed in chunks. This hint allows users to customized the chunk size. The default is 1048576 bytes, i.e. 1 MiB.
When file striping unit size is known after file create/open, and the hint nc_data_move_chunk_size is not set by users, the chunk size will be set to the striping size.
When moving variable sections, starting file offsets of all read and write chunks will be aligned with the hint nc_data_move_chunk_size.