vacuum job taking very long time to complete

I've started a vacuumdb on a database having 2 large tables of approx. 3,800,000 records each. The database size is approx . 2Gbyte

It generates a lot of logfiles, currently the pg_xlog directory has about 4.6 Gbyte of logfiles and when I started there were I guess 2 logfiles each 16 Megs.

I still have 3.5 G available for logfiles but suppose there is a chance that I will run out of diskspace before the vacuum is done , can I kill it safely before that happens ?

Thanks,

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Feite Brekeveld
feite.brekeveld@osiris-it.nl