Zugg Software :: View topic - [3.14] Strange issue with VIM and very large files in TESSH

Apprentice Joined: 16 Dec 2002 Posts: 114 Location: USA

Not sure how to explain it, but here goes:

When dealing with a massively large file in VIM (70k lines for instance), if you do certain actions, all text just... disappears so to speak.

In my case, I did a %s substitution, then GG.. and... screen went black.. I have seen this in earlier versions, but not sure what causes it. I can reliably reproduce it though.

Apprentice Joined: 16 Dec 2002 Posts: 114 Location: USA

Ok, so it seems that the issue relates to large files and jumping to the end with G, ( sorry, gg vs G ... anyway ). I have found that it is still operational, so you might want to be careful.

Full scenario:

1.) Login on machine
2.) Start a screen session
3.) ssh to a remote host (this way you can get back your localecho)
4.) Edit a MASSIVE file in vim
5.) jump from beginning of file to end of file (gg, G)
6.) Text goes black
7.) If comfortable, save the file if you made changes. If not, exit the file without write.
8.) exit the ssh session: Text returns.

Wanderer Joined: 28 Jan 2006 Posts: 60 Location: Scotland

What do you mean by:

Apprentice Joined: 16 Dec 2002 Posts: 114 Location: USA

screen is a session utility in linux. it allows you to manage multiple windows within one.

also, 90k isnt very large. the file I'm working with is 5.4MB, 70,000+ lines.

Wanderer Joined: 28 Jan 2006 Posts: 60 Location: Scotland

Apprentice Joined: 16 Dec 2002 Posts: 114 Location: USA

term is set to XTERM

Quick rundown of using screen (for purpose of this example).

Assuming its installed:

screen -S test (start a new session named test)
ssh somewhere
edit ridiculous large file until black (jump between the top and bottom using gg and G, never fails for me )
exit file
exit ssh connection (text will return)
exit again will close screen and your active connection

Posted: Mon Feb 15, 2010 5:53 pm

I'm also confused by the "screen" bit. You need to determine if this is a problem in TeSSH or in "screen". Can't you just use TeSSH to make an SSH connection to your remote server, then use VIM to edit a large file without screen to see if it works?

Not sure why you'd be using "screen" within CMUD since CMUD already lets you have multiple windows and sessions itself.

CMUD doesn't care how large a file is. When editing a file in VIM, VIM is only displaying the current page of the file on the screen. If you look at the raw input/output of a VIM session, you won't see any difference between a large file or a small file. So something else is going on here.

My guess is that some combination of "screen" and VIM is sending an xterm code to CMUD that CMUD is not emulating properly. What I would need to test this is the raw debug file from CMUD, which you can get by opening your CMUD session OFFLINE, then type:

#DEBUGFILE test.raw test.txt

in the CMUD command line. Then use File/Reconnect to connect to the session and do whatever steps you need to reproduce the bug. Then exit CMUD and send me both the test.raw and test.txt files as email attachments to sales@zuggsoft.com.

Apprentice Joined: 16 Dec 2002 Posts: 114 Location: USA

The reason for screen is so that when I start large and lengthy operations that take excess of 8 hours, I can leave them running in the foreground and come back to them later. Granted, I could just as easily bg them and resume them by bringing them to fg later, but screen is a very commonly used tool by sysadmins, it allows us to minimize the number of "windows" we have to open.

I'll see about getting the raw text to you later today.