Trying to go from 1.7.3.1 to 1.7.5 stable - Can't disable system caching

[rkk]

I can turn off smarty caching, but I can't turn off system caching. In system caching I change it to 'No' from the dropdown, it says success, but it reverts back to 'Yes'  The radio buttons for the type of caching are all disabled, with memcached selected.

When I try to add a memcached server (127.0.0.1 11211) the XHR request gets a 500 error 

Request URL: https://MYDOMAIN.com/admin4XXXXXX/index.php/configure/advanced/memcache/servers?_token=Lu5dh-Qd5KlVXXXXXXXXXXXXXXXXXXX

To get around this, in 'app/config/paramaters.php' I manually changed to 'ps_cache_enable' => 0.
Under performance, it still showed 'Yes' for system caching with radio buttons still disabled, but it allowed me to run the 1 click upgrade. 

I ran the 1 click upgrade and got the error "[Ajax / Server Error for action backupDb] textStatus: "error " errorThrown:"Service Unavailable " jqXHR: "

I rolled everything back and tried doing the same thing with every single file chmoded to 755 and then 777 with the same result. 

I'm running PHP 7.1 with suphp. I've also tried it with fcgi, and I've tried with with FPM turned on and also turned off.

 

Does anyone know where I should go from here? I'd love to figure out how to be able to configure my caching and get upgraded.

Thanks!

Edited April 9, 2019 by rkk
more descriptive title (see edit history)

[dev_to_much]

I have seen this, too. It looks like it is broken and there is now way around around :(

It won't let me configure eirher.

So we are stuck for now I guess...

[dev_to_much]

PrestaShop does not seem to care, they dismiss the issue: https://github.com/PrestaShop/PrestaShop/issues/12977