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> Dear Yuan: > > We have decided that Xvfb is simply broken in our 64-bit CentOS 5.5 > environment. We have started running an instance of the Xvnc VNC server > to provide the Xserver we need for our batch programs and it works fine > for us. I would encourage others to try Xvnc if they have trouble with > Xvfb. The intended purpose of Xvnc is to run a virtual > X session to which users can connect over the network. We are simply > running it for the X server to support batch IDV programs, though we > could connect to the server from a VNC client, if necessary for debugging. > > Here are some observations on the Xvfb issue: > > We gave up on Xvfb after concluding that it is broken, at least > the version which is provided with CentOS 5.5. We suspect > that it was not ported correctly to a 64-bit environment. > Perhaps it makes invalid assumption about the sizes of > data types -- something that is likely to be critical > for a program which handles a complex binary protocol. > > Some clues: > > A user of IDV reported that he was able to use Xvfb in a > 32-bit CentOS environment, but had no luck in a 64-bit installation. > > valgrind reports many, many errors when I run Xvfb on mopfl, > but none when I run it on my personal 32-bit Fedora system. > > Thanks for your help. > > Regards, > Vince Vince, Many thanks. I posted your discovery in our idv user list, and it will benefit many users. Yuan > > On 7/6/2010 1:02 PM, Unidata IDV Support wrote: > >> Dear Unidata team: > >> > >> We're attempting to run an IDV script as a batch process on a Linux > >> server without > >> depending on the graphics card. It appears we still need to give IDV > >> access to an X server, and we are trying to use Xvfb as that X server. > > > Vince, > > I don't have much experience of Xvfb, after browsing the support > > archive, one suggestion is to upgrade the Xvfb to newer version, here is a > > link of the IDV user discussion: > > > > http://www.unidata.ucar.edu/mailing_lists/archives/idvusers/2010/msg00002.html. > > > > > > Yuan > > > Ticket Details > > =================== > > Ticket ID: TDV-431327 > > Department: Support IDV > > Priority: Normal > > Status: Open > > > > > > -- > Vince Dean > HIRDLS Project - SIPS Operations Manager > University of Colorado > MOPITT Project - Data Manager > National Center for Atmospheric Research > Phone: (303) 497-8077 > > Ticket Details =================== Ticket ID: TDV-431327 Department: Support IDV Priority: High Status: Closed