Why does the `updatedb` program run so fast?
Usually when I have programs that are doing a full disk scan and going over all files in the system they take a very long time to run. Why does updatedb run so fast in comparison?
updatedb
asked 1 hour ago
hugomg
1,66731632
add a comment |
Usually when I have programs that are doing a full disk scan and going over all files in the system they take a very long time to run. Why does updatedb run so fast in comparison?
updatedb
asked 1 hour ago
hugomg
1,66731632
add a comment |
Usually when I have programs that are doing a full disk scan and going over all files in the system they take a very long time to run. Why does updatedb run so fast in comparison?
updatedb
asked 1 hour ago
hugomg
1,66731632
Usually when I have programs that are doing a full disk scan and going over all files in the system they take a very long time to run. Why does updatedb run so fast in comparison?
updatedb
updatedb
asked 1 hour ago
hugomg
1,66731632
asked 1 hour ago
hugomg
1,66731632
asked 1 hour ago
hugomg
1,66731632
asked 1 hour ago
hugomg
1,66731632
asked 1 hour ago
hugomg
1,66731632
1,66731632
add a comment |
add a comment |
1 Answer
1
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The answer depends on the version of locate you’re using, but there’s a fair chance it’s mlocate, whose updatedb runs quickly by avoiding doing full disk scans:
mlocate is a locate/updatedb implementation. The 'm' stands for "merging":
updatedb reuses the existing database to avoid rereading most of the file
system, which makes updatedb faster and does not trash the system caches as
much.
(The database stores each directory’s timestamp, ctime or mtime, whichever is newer.)
answered 1 hour ago
Stephen Kitt
164k24365444
Fairly good question and answer, did not even know there were "differencial" scannings.
– Rui F Ribeiro
1 hour ago
Thanks! I had never noticed that modifying a file also changes the ctime and mtime of all its parent directories.
– hugomg
7 mins ago
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
The answer depends on the version of locate you’re using, but there’s a fair chance it’s mlocate, whose updatedb runs quickly by avoiding doing full disk scans:
mlocate is a locate/updatedb implementation. The 'm' stands for "merging":
updatedb reuses the existing database to avoid rereading most of the file
system, which makes updatedb faster and does not trash the system caches as
much.
(The database stores each directory’s timestamp, ctime or mtime, whichever is newer.)
answered 1 hour ago
Stephen Kitt
164k24365444
Fairly good question and answer, did not even know there were "differencial" scannings.
– Rui F Ribeiro
1 hour ago
Thanks! I had never noticed that modifying a file also changes the ctime and mtime of all its parent directories.
– hugomg
7 mins ago
add a comment |
The answer depends on the version of locate you’re using, but there’s a fair chance it’s mlocate, whose updatedb runs quickly by avoiding doing full disk scans:
mlocate is a locate/updatedb implementation. The 'm' stands for "merging":
updatedb reuses the existing database to avoid rereading most of the file
system, which makes updatedb faster and does not trash the system caches as
much.
(The database stores each directory’s timestamp, ctime or mtime, whichever is newer.)
answered 1 hour ago
Stephen Kitt
164k24365444
Fairly good question and answer, did not even know there were "differencial" scannings.
– Rui F Ribeiro
1 hour ago
Thanks! I had never noticed that modifying a file also changes the ctime and mtime of all its parent directories.
– hugomg
7 mins ago
add a comment |
The answer depends on the version of locate you’re using, but there’s a fair chance it’s mlocate, whose updatedb runs quickly by avoiding doing full disk scans:
mlocate is a locate/updatedb implementation. The 'm' stands for "merging":
updatedb reuses the existing database to avoid rereading most of the file
system, which makes updatedb faster and does not trash the system caches as
much.
(The database stores each directory’s timestamp, ctime or mtime, whichever is newer.)
answered 1 hour ago
Stephen Kitt
164k24365444
The answer depends on the version of locate you’re using, but there’s a fair chance it’s mlocate, whose updatedb runs quickly by avoiding doing full disk scans:
mlocate is a locate/updatedb implementation. The 'm' stands for "merging":
updatedb reuses the existing database to avoid rereading most of the file
system, which makes updatedb faster and does not trash the system caches as
much.
(The database stores each directory’s timestamp, ctime or mtime, whichever is newer.)
answered 1 hour ago
Stephen Kitt
164k24365444
edited 1 hour ago
answered 1 hour ago
Stephen Kitt
164k24365444
answered 1 hour ago
Stephen Kitt
164k24365444
answered 1 hour ago
Stephen Kitt
164k24365444
164k24365444
Fairly good question and answer, did not even know there were "differencial" scannings.
– Rui F Ribeiro
1 hour ago
Thanks! I had never noticed that modifying a file also changes the ctime and mtime of all its parent directories.
– hugomg
7 mins ago
add a comment |
Fairly good question and answer, did not even know there were "differencial" scannings.
– Rui F Ribeiro
1 hour ago
Thanks! I had never noticed that modifying a file also changes the ctime and mtime of all its parent directories.
– hugomg
7 mins ago
Fairly good question and answer, did not even know there were "differencial" scannings.
– Rui F Ribeiro
1 hour ago
Fairly good question and answer, did not even know there were "differencial" scannings.
– Rui F Ribeiro
1 hour ago
Thanks! I had never noticed that modifying a file also changes the ctime and mtime of all its parent directories.
– hugomg
7 mins ago
Thanks! I had never noticed that modifying a file also changes the ctime and mtime of all its parent directories.
– hugomg
7 mins ago
add a comment |
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