Upgrade issue

Hi All

I seem to be having problems with upgrading a Perch version.

I upgraded a perch site from 2.5.4 to the latest version today and after I uploaded everything and logged in for it to do the upgrade as normal, all I had was a blank white screen with just 'Sofware Update' output to the screen and nothing else

In the php log, I had this:

[Fri Jan 09 21:01:20 2015] [error] [client 86.16.120.222:57457] AH01215: PHP Fatal error:  Allowed memory size of 134217728 bytes exhausted (tried to allocate 83 bytes) in /home/sites/xxxxxxxx.co.uk/public_html/site-login/core/lib/PerchDB_MySQL.class.php on line 185

I have obviously replaced the site with 'xxxxxxxx' and just to avoid confusion, I rename my perch directory to 'site-login'. I've not had an upgrade error before so I'm a bit lost!

I haven't yet rolled back to the backu in case there was any info from the database that might be needed,

Thanks, Michael