Java performance awful, any ideas?

Jordan Erickson jerickson at logicalnetworking.net
Fri Nov 14 23:17:08 GMT 2008


"The main difference between these versions appears to be that the Hardy version links

to /usr/lib/libxcb-xlib.so.0 and /usr/lib/libxcb.so.1, and the older version does not."




I'm guessing it has to do with that. I *just* did the Gutsy file copy today at one school, and it seemed to fix the problem all together with no ill effects (knocks on wood).


Cheers,
Jordan/Lns



Todd O'Bryan wrote:
> Does anyone have any idea what the bug might be and if it's still
> present in intrepid? I'll try the fix on Monday and see what
> happens...
>
> On Fri, Nov 14, 2008 at 10:05 AM, Kai Wollweber <wollw at ki.tng.de> wrote:
>   
>> Am Freitag, den 14.11.2008, 09:44 -0500 schrieb Todd O'Bryan:
>>
>>     
>>> I'm trying to run BlueJ (http://www.bluej.org), a fairly modest Java
>>> IDE for students. It runs fine on the servers, on my Ubuntu laptop and
>>> desktop, but on the clients it's as slow as molasses.
>>>       
>> Rhere is already a bug report at launchpad about this issue:
>>
>> https://bugs.launchpad.net/ubuntu/+source/ia32-libs/+bug/277069
>>
>>
>> I asked Juha in ltsp-discuss mailing-list and his answer gives us a
>> workaround:
>>
>>     
>>> ----- "Kai Wollweber" <wollw at ki.tng.de> kirjoitti:
>>>       
>>>> yesterday I recognized the problem of slow java applications on our
>>>>         
>>> ltsp
>>>       
>>>> clients. In our case the java program "geonext" is unuseable but
>>>> importand for our school. I found your solution posted some weeks
>>>> ago:
>>>>         
>>>>> The sluggishness of some Java applications can be solved in Ubuntu
>>>>> Hardy by replacing the /usr/lib32/libX11.so.6.2.0 file in Hardy
>>>>>           
>>> with
>>>       
>>>>> the version in Gutsy (presuming Firefox and Java are 32-bit
>>>>>           
>>> versions, so
>>>       
>>>>> they use 32-bit libraries).  The main difference between these
>>>>>           
>>> versions
>>>       
>>>>> appears to be that the Hardy version links
>>>>>           
>>> to /usr/lib/libxcb-xlib.so.0
>>>       
>>>>> and /usr/lib/libxcb.so.1, and the older version does not.  Similar
>>>>>           
>>> change
>>>       
>>>>> may work as well with other LTSP distributions that are affected by
>>>>>           
>>> this.
>>>
>>>       
>>>> 1.) How can a single file be replaced between different Ubuntu
>>>>         
>>> versions?
>>>
>>> Simply replacing the file (with cp) should be enough, but in
>>> case updates should happen to ia32-libs package that contains the
>>> /usr/lib32/libX11.so.6.2.0 file, those updates will overwrite the
>>> changed file.  dpkg-divert can be used to solve this problem, it can
>>> be used to divert file updates to another place (in this case, because
>>> the file is a shared library, it should not be in the same directory,
>>> otherwise ldconfig will link to the wrong file).
>>>
>>> You might want to test by simply installing the gutsy version of
>>> ia32-libs package, it should work, but I don't recommend that as a
>>> permanent solution (it will change many other libraries as well).
>>>
>>>       
>>>> 2.) Where can I get the file from Gutsy?
>>>>         
>>> http://packages.ubuntu.com/gutsy-updates/amd64/ia32-libs/download
>>>
>>> You can unpack deb-archives with (IIRC):
>>>
>>> (mkdir tmp && cd tmp && ar x ../ia32-libs_2.1ubuntu4_amd64.deb && \
>>>    tar -zxf data.tar.gz)
>>>
>>> You'll find the file there.
>>>
>>>       
>>>> 3.) Are there side effects that probably can affect the system?
>>>>         
>>> Perhaps, but I'm not aware of any.
>>>
>>>       
>>>> 4.) Am I right that the file needs to be replaced in the ltsp
>>>>         
>>> chroot?
>>>
>>> No, X-clients use this library, so it needs to be replaced in the ltsp
>>> server environment, NOT in the image that is served to terminals.
>>>
>>> I hope this helps.
>>>
>>> Juha
>>>       
>> --
>> edubuntu-users mailing list
>> edubuntu-users at lists.ubuntu.com
>> Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/edubuntu-users
>>
>>     
>
>   


-- 
Jordan Erickson
Owner, Logical Networking Solutions
http://www.logicalnetworking.net
707-636-5678

Latest LNS Blogs - http://blogs.logicalnetworking.net

	Intel and HP team up to roll out Green PCs for the enterprise
	Mozilla Thunderbird Add-on "Signature Switch"
	Will "Windows 7" be another Mojave Experiment?




More information about the edubuntu-users mailing list