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I just thought I would pass on a trick that Paul Adams and Nigel Moriarty 
pointed out recently.  That was in the context of the Phenix interface, but 
it applies equally to ccp4i.

If you've ever tried to run ccp4i over the network using ssh and X forwarding, 
you might have been discouraged by how slow it becomes, particularly with 
anything less than the fastest connections.  I had almost given up on running 
ccp4i when connecting from home via broadband (2Mb connection, which is fast 
enough for most other things).

Nigel looked into this problem and found out that the speed of X forwarding 
can be increased dramatically by turning on compression when running ssh 
(using the -C flag).  Perhaps this is no news to many of you, but I had 
certainly missed that flag in the documentation.  As an illustration of the 
size of the effect, it takes 260 seconds to open the Phaser molecular 
replacement GUI without the -C flag on my home connection, but only 33 
seconds with the -C flag.  Still slow, but bearable.

On either an iBook running OSX 10.3 or a laptop running Fedora Core 4, the 
command I use to connect is:

ssh -X -C [EMAIL PROTECTED]

The -X flag may not be required, depending on the setup, but says to turn
on X forwarding.  Paul Adams says that this doesn't work for some connections, 
in which case replacing "-X" by "-Y" might work.  This turns off some 
security checks and may get around firewall issues.

Presumably there are equivalent flags when connecting from non-Unix-based 
machines, but I don't have an X client on my Windows machines; perhaps 
someone else can comment.

-- 

Randy J. Read
Department of Haematology, University of Cambridge
Cambridge Institute for Medical Research      Tel: + 44 1223 336500
Wellcome Trust/MRC Building                   Fax: + 44 1223 336827
Hills Road                                    E-mail: [EMAIL PROTECTED]
Cambridge CB2 2XY, U.K.                       www-structmed.cimr.cam.ac.uk


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