Problem in upgrading from 4.2.3 to 5.1.7

[Oracle simsim]

Hello
Overview:
I have large forum (more than 3 million posts) and blog (more than 120 thousand entry). Current version is 4.2.3 beta which I intend to upgrade to 5.1.7 latest beta.

The steps:

1. Create a full copy of the original Database and upload it with name vb5
2. Create an empty directory "/forum".
3. Modify the two config.php files with the appropriate values to connect to the database besides adjusting other settings
4. upload the "upload" folder to the empty directory in my host.
5. run the upgrade script through cli "php upgrade.php"
6. Everything is fine and the upgrade run smoothly rhrouch the steps and updating the database until ...

Upgrading to 5.0.0 Alpha 22
----------------------------------
Step 1 - Importing data from blog
         Processed 500 records
Importing data from blog
         Processed 500 records
Importing data from blog
         Processed 500 records

the upgrader stuck on this steps forever. I can see there is no updates to the database

Also the cpu consumption is high. (more than 50%) which mean it maybe running in deadlock

what should I do ?

also I stopped the script by myself (Ctrl+C) so I don't know if this may lead to corrupted data (thank for God that it is only a test)

[Wayne Luke]

That step is going to run for a while. It could be a few hours depending on your server setup. You said you have over 120,000 blog entries and it is doing 500 entries each time. It will have to repeat at least 240 times.

[Oracle simsim]

OK thanks I will try again. Though I believe that there is a problem because the 3 millions posts finish in two hours so the 120k entries should finish quickly specially my server is very good.

[Oracle simsim]

I let it run for more than 45 only in this step then:
Fatal error: Allowed memory size of 268435456 bytes exhausted (tried to allocate 591289 bytes) in /home/user/public_html/forum/core/vb/db/querybuilder.php on line 495

[Trevor Hannant]

To increase your limits edit your includes/config.php file and add these lines right under the <?php line:

ini_set('memory_limit', -1);
ini_set("max_execution_time", "2880");

Then refresh the page. If you have the same problem after that, you need to contact your host and ask them to check the server error logs.