rsync: Why is “quick check” default but “--times” is not?
Clash Royale CLAN TAG#URR8PPP
rsync's manpage states:
Rsync finds files that need to be transferred using a "quick check" algorithm (by default) that looks for files that have changed in size or in last-modified time. Any changes in the other preserved attributes (as requested by options) are made on the destination file directly when the quick check indicates that the file's data does not need to be updated.
So for a file to be skipped the modification time has to be the same in source and destination. But since --times is off by default, the destination files will get the time of the sync as their modification time, causing them to be transferred over and over again.
Especially the fact that that paragraph says (emphasis mine):
... Any changes in the other preserved attributes ...
makes it appear (to me) as if the modification time was already a preserved attribute by default, but in my experiment I found otherwise.
What am I missing?
rsync
asked Jan 11 at 21:31
AndreKRAndreKR
373421
add a comment |
rsync's manpage states:
Rsync finds files that need to be transferred using a "quick check" algorithm (by default) that looks for files that have changed in size or in last-modified time. Any changes in the other preserved attributes (as requested by options) are made on the destination file directly when the quick check indicates that the file's data does not need to be updated.
So for a file to be skipped the modification time has to be the same in source and destination. But since --times is off by default, the destination files will get the time of the sync as their modification time, causing them to be transferred over and over again.
Especially the fact that that paragraph says (emphasis mine):
... Any changes in the other preserved attributes ...
makes it appear (to me) as if the modification time was already a preserved attribute by default, but in my experiment I found otherwise.
What am I missing?
rsync
asked Jan 11 at 21:31
AndreKRAndreKR
373421
add a comment |
rsync's manpage states:
Rsync finds files that need to be transferred using a "quick check" algorithm (by default) that looks for files that have changed in size or in last-modified time. Any changes in the other preserved attributes (as requested by options) are made on the destination file directly when the quick check indicates that the file's data does not need to be updated.
So for a file to be skipped the modification time has to be the same in source and destination. But since --times is off by default, the destination files will get the time of the sync as their modification time, causing them to be transferred over and over again.
Especially the fact that that paragraph says (emphasis mine):
... Any changes in the other preserved attributes ...
makes it appear (to me) as if the modification time was already a preserved attribute by default, but in my experiment I found otherwise.
What am I missing?
rsync
asked Jan 11 at 21:31
AndreKRAndreKR
373421
rsync's manpage states:
Rsync finds files that need to be transferred using a "quick check" algorithm (by default) that looks for files that have changed in size or in last-modified time. Any changes in the other preserved attributes (as requested by options) are made on the destination file directly when the quick check indicates that the file's data does not need to be updated.
So for a file to be skipped the modification time has to be the same in source and destination. But since --times is off by default, the destination files will get the time of the sync as their modification time, causing them to be transferred over and over again.
Especially the fact that that paragraph says (emphasis mine):
... Any changes in the other preserved attributes ...
makes it appear (to me) as if the modification time was already a preserved attribute by default, but in my experiment I found otherwise.
What am I missing?
rsync
rsync
asked Jan 11 at 21:31
AndreKRAndreKR
373421
asked Jan 11 at 21:31
AndreKRAndreKR
373421
asked Jan 11 at 21:31
AndreKRAndreKR
373421
asked Jan 11 at 21:31
AndreKRAndreKR
373421
asked Jan 11 at 21:31
AndreKRAndreKR
373421
373421
add a comment |
add a comment |
1 Answer
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"(as requested by options)"
Yes, the word "other" in the sentence makes your interpretation possible, but I think that the actual situation is that there are no preserved attributes by default, and that these need to be explicitly requested by options.
rsync works very much like cp in this regard, which also does not preserve timestamps or ownerships on files by default. Both preserves permissions though.
answered Jan 11 at 21:55
KusalanandaKusalananda
127k16239393
Indeed, I cannot come up with a better default that would keep the similarity withcp.
– AndreKR
Jan 12 at 1:33
add a comment |
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1 Answer
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1 Answer
1
active
oldest
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active
oldest
votes
"(as requested by options)"
Yes, the word "other" in the sentence makes your interpretation possible, but I think that the actual situation is that there are no preserved attributes by default, and that these need to be explicitly requested by options.
rsync works very much like cp in this regard, which also does not preserve timestamps or ownerships on files by default. Both preserves permissions though.
answered Jan 11 at 21:55
KusalanandaKusalananda
127k16239393
Indeed, I cannot come up with a better default that would keep the similarity withcp.
– AndreKR
Jan 12 at 1:33
add a comment |
"(as requested by options)"
Yes, the word "other" in the sentence makes your interpretation possible, but I think that the actual situation is that there are no preserved attributes by default, and that these need to be explicitly requested by options.
rsync works very much like cp in this regard, which also does not preserve timestamps or ownerships on files by default. Both preserves permissions though.
answered Jan 11 at 21:55
KusalanandaKusalananda
127k16239393
Indeed, I cannot come up with a better default that would keep the similarity withcp.
– AndreKR
Jan 12 at 1:33
add a comment |
"(as requested by options)"
Yes, the word "other" in the sentence makes your interpretation possible, but I think that the actual situation is that there are no preserved attributes by default, and that these need to be explicitly requested by options.
rsync works very much like cp in this regard, which also does not preserve timestamps or ownerships on files by default. Both preserves permissions though.
answered Jan 11 at 21:55
KusalanandaKusalananda
127k16239393
"(as requested by options)"
Yes, the word "other" in the sentence makes your interpretation possible, but I think that the actual situation is that there are no preserved attributes by default, and that these need to be explicitly requested by options.
rsync works very much like cp in this regard, which also does not preserve timestamps or ownerships on files by default. Both preserves permissions though.
answered Jan 11 at 21:55
KusalanandaKusalananda
127k16239393
edited Jan 11 at 22:01
answered Jan 11 at 21:55
KusalanandaKusalananda
127k16239393
answered Jan 11 at 21:55
KusalanandaKusalananda
127k16239393
answered Jan 11 at 21:55
KusalanandaKusalananda
127k16239393
127k16239393
Indeed, I cannot come up with a better default that would keep the similarity withcp.
– AndreKR
Jan 12 at 1:33
add a comment |
Indeed, I cannot come up with a better default that would keep the similarity withcp.
– AndreKR
Jan 12 at 1:33
Indeed, I cannot come up with a better default that would keep the similarity with
cp.– AndreKR
Jan 12 at 1:33
Indeed, I cannot come up with a better default that would keep the similarity with
cp.– AndreKR
Jan 12 at 1:33
add a comment |
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