Q:

Memcache module is working but with a strange error

I have Memcache enabled both on Drupal and the server... It seems to be configured fine on the server-end (both by port & Settings.php).
If am being accurate, PSI grades even went up in about 4-5 points... So seemingly my site does use Memcache... And yet, Cron gives a strange error:

PECL Memcache version 2.2.5 is unsupported. Please update to 3.0.6 or
  newer.

Tried to Google the error (or part of it) and found just nothing... I've also spoke with the server's support team and one of them told me to ignore this error... I'm not sure if this is the right thing to do... Will glad for the advice of Veteran drupal developers...

A:

"Not supported" doesn't necessarily mean that it shouldn't work at all. I guess in this case it only means you shouldn't complain in case something breaks.
You may want to check if you can install a newer version of Memcache on your platform, just to be sure and future-proof.

