I am confused by the differences in the time between updates of different repositories in the same machines and of the same repository in different machines. I am using the assistant (in all machines, 'git annex assitant --autostart').

For instance, I have three machines synced as

A <-> B <-> C

and I have two directories being synced. The configuration (except for directory names) is the same and looks like

[annex]
        uuid = something
        version = 5
        direct = true
        autoupgrade = true
        autocommit = true
        startupscan = true
[remote "machine_repo"]
        url = ssh://xxxxxx/~/repo/
        fetch = +refs/heads/*:refs/remotes/machine_repo/*
        annex-uuid = xxxxxxxxxxxxx

I modify or add a file in one of the directories in A, and it quickly (less than 30 seconds) appears in B and shortly after that in C.

In another directory, however, more than 30 minutes can go by without C ever changing (even if B gets the change almost immediately). Looking at the logs I cannot understand what is happening. This is the case of a file, A_sentinel_file_A, created at 01:46.

In B (where it appears almost immediately) I can see

[2015-03-02 01:46:17 CET] Pusher: Syncing with 123.456.789.101_somedir 
To ssh://ramon@git-annex-Machine_C-ramon_22_annex.2Done.2Dway.2F/~/some-dir/
   794df9f..ae8c3f0  git-annex -> synced/git-annex
Automatic merge went well; stopped before committing as requested
[2015-03-02 01:47:03 CET] Committer: Committing changes to git
[2015-03-02 01:47:03 CET] Pusher: Syncing with 123.456.789.101_somedir 

A_sentinel_file_A
             18 100%    0.00kB/s    0:00:00 (xfr#1, to-chk=0/1)
[2015-03-02 01:47:04 CET] Transferrer: Uploaded A_sentinel_file_A
To ssh://ramon@git-annex-Machine_C-ramon_22_annex.2Done.2Dway.2F/~/some-dir/
   ae8c3f0..b043335  git-annex -> synced/git-annex
   75269bc..b61c7a5  annex/direct/master -> synced/master
[2015-03-02 01:47:04 CET] Committer: Committing changes to git
[2015-03-02 01:47:06 CET] Pusher: Syncing with 123.456.789.101_somedir 
To ssh://ramon@git-annex-Machine_C-ramon_22_annex.2Done.2Dway.2F/~/some-dir/
   b043335..fc9279c  git-annex -> synced/git-annex

And in C (the machine with IP 123.456.789.101, above) I can see

[2015-03-02 01:46:13 CET] RemoteControl: Syncing with Machine_B_somedir 
From ssh://git-annex-Machine_B-ramon_22_annex.2Done.2Dway/~/some-dir
   593d908..794df9f  git-annex  -> Machine_B_somedir/git-annex
   593d908..235149d  synced/git-annex -> Machine_B_somedir/synced/git-annex
   a1596b3..75269bc  synced/master -> Machine_B_somedir/synced/master
[2015-03-02 01:46:17 CET] RemoteControl: Syncing with Machine_B_somedir 
From ssh://git-annex-Machine_B-ramon_22_annex.2Done.2Dway/~/some-dir
   a1596b3..75269bc  annex/direct/master -> Machine_B_somedir/annex/direct/master
   794df9f..ae8c3f0  git-annex  -> Machine_B_somedir/git-annex
   a1596b3..75269bc  master     -> Machine_B_somedir/master
[2015-03-02 01:46:27 CET] RemoteControl: Syncing with Machine_B_somedir 
From ssh://git-annex-Machine_B-ramon_22_annex.2Done.2Dway/~/some-dir
   ae8c3f0..632caa4  git-annex  -> Machine_B_somedir/git-annex
   235149d..632caa4  synced/git-annex -> Machine_B_somedir/synced/git-annex
[2015-03-02 01:47:02 CET] RemoteControl: Syncing with Machine_B_somedir 
From ssh://git-annex-Machine_B-ramon_22_annex.2Done.2Dway/~/some-dir
   632caa4..56ac968  synced/git-annex -> Machine_B_somedir/synced/git-annex
   75269bc..b61c7a5  synced/master -> Machine_B_somedir/synced/master
[2015-03-02 01:47:02 CET] RemoteControl: Syncing with Machine_B_somedir 
From ssh://git-annex-Machine_B-ramon_22_annex.2Done.2Dway/~/some-dir
   632caa4..b043335  git-annex  -> Machine_B_somedir/git-annex
[2015-03-02 01:47:07 CET] RemoteControl: Syncing with Machine_B_somedir 
From ssh://git-annex-Machine_B-ramon_22_annex.2Done.2Dway/~/some-dir
   75269bc..b61c7a5  annex/direct/master -> Machine_B_somedir/annex/direct/master
   b043335..fc9279c  git-annex  -> Machine_B_somedir/git-annex
   75269bc..b61c7a5  master     -> Machine_B_somedir/master
[2015-03-02 01:47:15 CET] RemoteControl: Syncing with Machine_B_somedir 
From ssh://git-annex-Machine_B-ramon_22_annex.2Done.2Dway/~/some-dir
   fc9279c..a4642a8  git-annex  -> Machine_B_somedir/git-annex
   56ac968..a4642a8  synced/git-annex -> Machine_B_somedir/synced/git-annex
(merging synced/git-annex Machine_B_somedir/git-annex into git-annex...)
(recording state in git...)
[2015-03-02 02:17:23 CET] RemoteControl: Syncing with Machine_B_somedir 
From ssh://git-annex-Machine_B-ramon_22_annex.2Done.2Dway/~/some-dir
   a4642a8..bfaba72  git-annex  -> Machine_B_somedir/git-annex
   a4642a8..bfaba72  synced/git-annex -> Machine_B_somedir/synced/git-annex
   b61c7a5..29ff91e  synced/master -> Machine_B_somedir/synced/master   

Why did Machine C did not show the updated file at 01:47, which is when, I think, machine B pushes it there? Or at 02:17 when both machines again seem to talk to each other? Regardless, at 02:27 the file still was not there. Yes, of course, if I issue a

git annex sync --content

then the file is shown in Machine C. But I should not need to do that.

In contrast, as I said, there is another directory, with identical configuration, where these things do not happen and changes show immediately (both directories, for now, only have tiny test files).

What am I doing wrong? This is too big a difference to make sense to me.