Details
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New Feature
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Resolution: Unresolved
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Major
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None
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None
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9223372036854775807
Description
Request to enhance the functionality of "lfs setdirstripe" to allow the selection of specific MDTs in the default layout as opposed to only the starting MDT and count.
The current implementation allows for stripe on a specific series of MDTs, e.g.:
# lfs mkdir [-c 4] -i 1,2,4,6 /some/dir
but not to set this as the default layout on a parent directory:
# lfs setdirstripe -D [-c 4] -i 1,2,4,6 /some/dir lfs setdirstripe: cannot create stripe dir '/some/dir': Invalid argument
This should stripe subdirectories of /some/dir across 4 MDTs with the specified indexes.
Currently, the --stripe_count|-c and number of specified MDT indices need to match (the -c argument is implicitly set to the number of MDTs specified if not given).
It would be useful to allow specifying a subset of MDTs for allocation in some cases, either to keep a directory tree on a small subset of MDTs for admin/performance/locality reasons, or during migration to avoid striping a whole tree across all of the specified MDTs, while avoiding over-full MDTs:
lfs setdirstripe -D -c1 -i 1,3,5,7 /some/dir
This should stripe to only one of 4 specified MDTs with the indexes 1, 3, 5 & 7
This will allow for more controllable striping in a case where a file system could have many MDTs across many systems, and in cases where multiple MDTs may exist on one server, or some clients may be closer to specific MDTs than others.
Attachments
Issue Links
Activity
| Fix Version/s | Original: Lustre 2.11.0 [ 13091 ] | |
| Fix Version/s | Original: Lustre 2.12.0 [ 13495 ] |
| Description |
Original:
Request to enhance the functionality of "lfs setdirstripe" to include the selection of specific MDT's as appose to a series.
The current implementation allows for stripe on a series of MDT's, e.g.: {noformat} lfs setdirstripe -D -i 0 -c 4 /some/dir {noformat} *This will stripe to 4 MDT's at the start index of MDT0.* I am proposing we enhance this to stripe to multiple specific MDT's, e.g.: {noformat} lfs setdirstripe -D -i 1,3,5,7 /some/dir {noformat} *This will stripe over 4 specific MDT's with the indexes 1, 3, 5 & 7 - in which case no start index would be required.* {noformat} lfs setdirstripe -D -c1 -i 1,3,5,7 /some/dir {noformat} *This will stripe to one of 4 specific MDT's with the indexes 1, 3, 5 & 7* This will allow for more controllable striping in a case where a file system could have many MDT's across many systems and in cases where multiple MDT's may exist on one server. |
New:
Request to enhance the functionality of "{{lfs setdirstripe}}" to allow the selection of specific MDTs in the default layout as opposed to only the starting MDT and count.
The current implementation allows for stripe on a specific series of MDTs, e.g.: {noformat} # lfs mkdir [-c 4] -i 1,2,4,6 /some/dir {noformat} but not to set this as the default layout on a parent directory: {noformat} # lfs setdirstripe -D [-c 4] -i 1,2,4,6 /some/dir lfs setdirstripe: cannot create stripe dir '/some/dir': Invalid argument {noformat} *This should stripe subdirectories of {{/some/dir}} across 4 MDTs with the specified indexes.* Currently, the {{--stripe_count|-c}} and number of specified MDT indices need to match (the {{-c}} argument is implicitly set to the number of MDTs specified if not given). It would be useful to allow specifying a subset of MDTs for allocation in some cases, either to keep a directory tree on a small subset of MDTs for admin/performance/locality reasons, or during migration to avoid striping a whole tree across all of the specified MDTs, while avoiding over-full MDTs: {noformat} lfs setdirstripe -D -c1 -i 1,3,5,7 /some/dir {noformat} *This should stripe to only one of 4 specified MDTs with the indexes 1, 3, 5 & 7* This will allow for more controllable striping in a case where a file system could have many MDTs across many systems, and in cases where multiple MDTs may exist on one server, or some clients may be closer to specific MDTs than others. |
| Description |
Original:
Request to enhance the functionality of "lfs setdirstripe" to include the selection of specific MDT's as appose to a series. The current implementation allows for stripe on a series of MDT's, e.g.: {noformat} lfs setdirstripe -D -i 0 -c 4 /some/dir {noformat} *This will stripe to 4 MDT's at the start index of MDT0.* I am proposing we enhance this to stripe to multiple specific MDT's, e.g.: {noformat} lfs setdirstripe -D -o 1,3,5,7 /some/dir {noformat} *This will stripe to 4 specific MDT's with the indexes 1, 3, 5 & 7 - in which case no start index would be required.* This will allow for more controllable striping in a case where a file system could have many MDT's across many systems and in cases where multiple MDT's may exist on one server. |
New:
Request to enhance the functionality of "lfs setdirstripe" to include the selection of specific MDT's as appose to a series.
The current implementation allows for stripe on a series of MDT's, e.g.: {noformat} lfs setdirstripe -D -i 0 -c 4 /some/dir {noformat} *This will stripe to 4 MDT's at the start index of MDT0.* I am proposing we enhance this to stripe to multiple specific MDT's, e.g.: {noformat} lfs setdirstripe -D -i 1,3,5,7 /some/dir {noformat} *This will stripe over 4 specific MDT's with the indexes 1, 3, 5 & 7 - in which case no start index would be required.* {noformat} lfs setdirstripe -D -c1 -i 1,3,5,7 /some/dir {noformat} *This will stripe to one of 4 specific MDT's with the indexes 1, 3, 5 & 7* This will allow for more controllable striping in a case where a file system could have many MDT's across many systems and in cases where multiple MDT's may exist on one server. |
| Assignee | Original: Lai Siyao [ laisiyao ] | New: WC Triage [ wc-triage ] |