Inotify IN_CLOSE_WRITE results in many useless calls to rsync

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Write application that opens file with read and write privileges allowed
2. Run application, the app should open the file and NOT write to it, then 
close the file.
3. An IN_CLOSE_WRITE inotify event will be raised, however the modifications 
will have been made and modified timestamp will not have been changed on file 
either.

What is the expected output? What do you see instead?
No synchronization should occur as nothing has been modified.  Instead I see 
lsyncd calling rsync due to 'new/modified files/dirs'.

What version of the product are you using? On what operating system?
Using version 2.0.4.  Centos 5.6 OS, 2.6.18-238.9.1.el5 x86_64

Please provide any additional information below.

Lsyncd has been working marvelous for us.  The downfall after upgrading to 
version 2.0.4 from the 1.3.x branch is the fact that Lsync now makes use of 
IN_CLOSE_WRITE events rather than IN_MODIFY.  I see the advantages to using 
this method, however in my scenario it is causing a lot of useless rsync calls.

In particular when lsync is monitorying SVN repositories it is receiving a 
IN_CLOSE_WRITE notification on svn/db/rep-cache.db every 1 minute.  I'm not 
sure what process is accessing this file, nonetheless it appears to be opening 
the file with write privileges but does not write to the file every minute that 
it opens it.

Example c++ app to test with:
#include <iostream>
#include <fstream>
using namespace std;

int main()
{
    // open file ''test.txt'' for reading and writing
    filebuf buffer;
    ostream output(&buffer);
    istream input(&buffer);
    buffer.open ("test.txt", ios::in | ios::out );
    // Do not actually write anything to the file, just close it.
    buffer.close();
}

Original issue reported on code.google.com by randy.re...@gmail.com on 23 May 2011 at 9:05

[GoogleCodeExporter]

I'll make the inotify events Lsyncd listens to configureable.

Original comment by axk...@gmail.com on 26 May 2011 at 11:26

[GoogleCodeExporter]

I added it to SVN, please try.

 settings.inotifyMode = "Modify";

Should do what you want.

 settings.inotifyMode = "CloseWrite";

Is what currently is default.

 settings.inotifyMode = "CloseWrite or Modify";

Listens to both.

 settings.inotifyMode = "CloseWrite after Modify";

Not going to implemented soon, but might be done in future. Recognize a change 
when a CLOSE_WRITE comes after a MODIFY.

Original comment by axk...@gmail.com on 11 Jun 2011 at 4:38

• Changed state: Fixed