Re: Two weirdnesses (bugs ?) in tramp 2.0.34

[Kai Großjohann]

Gilbert Grosdidier <address@hidden> writes:

> On Wed, 13 Aug 2003, Kai Großjohann wrote:
>
>> Gilbert Grosdidier <address@hidden> writes:
>> 
>> > - major problem is: when trying to "save" a file towards the remote host, 
>> > it 
>> > always take several 10's of sec. with the message 
>> > "Waiting for remote host to process data" displayed in the minibuffer.
>> 
>> What's the value of tramp-chunksize after you do that?
>
> gg= This variable is "nil", both before and after a save.

OK.  So it's not the obvious thing.

>> Does the time depend on the file size, or is it (more or less) the
>> same for all files?  (If a twice-as-large file also takes twice as
>
> gg= It does not seem to depend on file size, although they are always quite 
> small.

So it seems that there is some overhead which is not relating to a
file.

Do you use an inline method such as ssh or an out of band method such
as scp or rsync?  If transfer of file contents is slow via scp/rsync,
then you might wish to try the corresponding inline method; I guess
it will be quite a bit faster for small files.  (Whenever you
transfer a file via scp, it has to do the ssh connection-setup
handshake, which takes a while.)

>> long, we can hypothesize that the problem could be the transfer of
>> the file contents; otherwise we need to look somewhere else.)
>> 
>> Tramp is not /that/ slow for me.
>> 
>> It takes a while to open a connection, but presumably the connection
>> is already open when you are saving...
>
> gg= IMHO, the connection is always already open when achieving a save:
> I usually open a Xemacs session, then fetch a remote file,
> edit and save several times over many hours ... Don't know what the exact
> duty cycle of tramp is: is it re-opening a connection after some delay 
> of "non-activity" ?

Tramp opens a connection using ssh or rsh or whatever, and then tries
to use the shell if possible.  But sometimes the remote host hangs up
after some period of inactivity.  You can try this yourself: log in
to the remote host manually, from outside Emacs, then see if the
connection is terminated after a while if you don't use it.

I guess 30 or 60 minutes would be a reasonable time for the
idle-logout.  But it depends on the admin of the remote host.

I guess this was obvious, but Tramp looks to see if the connection is
still open.  If it is, the old connection is reused.  If the
connection is closed, then Tramp opens another one, perhaps asking
you for a password.
-- 
Two cafe au lait please, but without milk.