There is a bug in the zf1/library/Zend/Cache/Backend/TwoLevels.php class which is setting the lifetime for the fast cache _getFastLifetime function.

It always set the lifetime to infinite (to null which is casted to 0) regardless the $lifetime parameter because of the default value of the $maxLifetime = null.

###The resposible condition part of the code as follow:

if ($maxLifetime >= 0 && $fastLifetime > $maxLifetime) {
            return $maxLifetime;
}

which will always evalute to true because of the default value of the $maxLifetime = null.

the issue faced while developing with memcached in Magento 2.2.5.

this is an bug in Zend framework 1 and it solved in early Zend framework 2
Links of the bug:

• https://framework.zend.com/issues/browse/ZF-11524
• Zend_Cache_Backend_TwoLevels fast backend lifetime always set to infinite on cache save zendframework/zf1#503

but I solved same as how it solved in ZF2 :

• https://github.com/beberlei/zf2/blob/master/library/Zend/Cache/Backend/TwoLevels.php