Hi Jongmin, Do you have some examples in mind of POSIX operations that will use the metadata logging functionality? thanks, -Phil On 11/24/2014 06:25 PM, Gim Jongmin wrote:
Dear All,
Last week, we are trying to design a metadata logging to support a transaction, which is enable to support write completion for related multiple write, i..e, updating metadata with its parent metadata. We analyzed FUSE operation when read and write requests are arrived, and write code for a log pool. Also we are inserting a code to check whether the logging transaction is properly working or not. This work will be continued in this week.
Sincerely, Jongmin
-- Jongmin Gim Post-Doctoral Research Associate Dept. of Elecrical and Computer Enginerring Texas A&M University 333B Wisenbaker College Station, TX 77843-3259 Phone: 979-587-8311
Hi Phil, This is an example. A client sends create(a/b/c). However, the directory 'a' and 'b' are not exist yet. In this situation, POSIX tries to create the directory, it depends on create option, finally, this create request implies mkdir 'a' , mkdir 'b', and create 'c' at the same time. If we consider these operations individually, we can create 3 logs for dir 'a', dir 'b', and file 'c'. If we met a failure to write dir 'b', we are able to recover dir 'b' by the logging. However, it may be failed for the request from the client application since we could not recover file 'c'. So we want to make a transaction for the request in the client FS layer. In the first place, we do not send each write to server before finishing the transaction. The log buffer holds it and write the log to server with just 1 write request. For this, we have to put these 3 metadata on single array by marshalling/unmarshalling and treat these as one I/O request. If it was success, we are able to recover dir 'a', dir 'b', and file 'c'. If the log writing was failed, it is same to 'undo'. The inconsistency for the request may be solved by this suggestion. We want to provide a transaction write for updating some related files. I am writing a sample code now and also have a room for the redesign. Thanks, Jongmin On Tue, Nov 25, 2014 at 7:45 PM, Phil Carns <[email protected]> wrote:
Hi Jongmin,
Do you have some examples in mind of POSIX operations that will use the metadata logging functionality?
thanks, -Phil
On 11/24/2014 06:25 PM, Gim Jongmin wrote:
Dear All,
Last week, we are trying to design a metadata logging to support a transaction, which is enable to support write completion for related multiple write, i..e, updating metadata with its parent metadata. We analyzed FUSE operation when read and write requests are arrived, and write code for a log pool. Also we are inserting a code to check whether the logging transaction is properly working or not. This work will be continued in this week.
Sincerely, Jongmin
-- Jongmin Gim Post-Doctoral Research Associate Dept. of Elecrical and Computer Enginerring Texas A&M University 333B Wisenbaker College Station, TX 77843-3259 Phone: 979-587-8311
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-- Jongmin Gim Post-Doctoral Research Associate Dept. of Elecrical and Computer Enginerring Texas A&M University 333B Wisenbaker College Station, TX 77843-3259 Phone: 979-587-8311
participants (2)
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Gim Jongmin -
Phil Carns