hg update failed after clone. it's huge repo

[ruby]

hi, I cloned a huge repo. 

after I faild many times, I finally got a full HG repo. (using hggit)

but it faild when updating.

I tried these  commands: 
hg state , good,
hg tip , good
hg log, good
hg update , failed

the .hg directory is huge, 1.5GB

so Hg update command cannot handle 1.5GB repo?
how to debug?

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I got this huge repo by this command:
hg clone clone git://xbmc.git.sourceforge.net/gitroot/xbmc/skins