关于Yii2使用memcache时的一个底层bug [ 技术分享 ]

memcache::set() - You can also use Unix timestamp or a number of seconds starting from current time, but in the latter case the number of seconds may not exceed 2592000 (30 days).

memcached::set() - The expiration time, defaults to 0. See Expiration Times for more info.

Some storage commands involve sending an expiration value (relative to an item or to an operation requested by the client) to the server. In all such cases, the actual value sent may either be Unix time (number of seconds since January 1, 1970, as an integer), or a number of seconds starting from current time. In the latter case, this number of seconds may not exceed 606024*30 (number of seconds in 30 days); if the expiration value is larger than that, the server will consider it to be real Unix time value rather than an offset from current time.

If the expiration value is 0 (the default), the item never expires (although it may be deleted from the server to make place for other items).

protected function setValue($key, $value, $duration)
{
    $expire = $duration > 0 ? $duration + time() : 0;

    return $this->useMemcached ? $this->_cache->set($key, $value, $expire) : $this->_cache->set($key, $value, 0, $expire);
}

这是yii2本来的代码

我知道你的意思，这是yii2的一个bug，和你所说的set时间无关哦

刚又想了想，如果memcache和memcached的set都可以传时间戳的话，那么可能是我的memcache的版本的问题导致传时间戳进去不起作用，而只支持传秒数进去，但是网上看到很多phper都遇到这样的问题，所以我目前更支持把$expire改成$duration，这样不管是用memcache还是memcached都正确

应该是没bug的。memcache和memcached都可以是到期时间戳，传秒数，setValues会转成到期时间戳。

我最近也遇到这个问题， 我怀疑原因是， 过期时间被 yii的setValue函数设置成了 time()+$duration, 假如memcache服务器时间比本地时间快60s， 这时缓存就会失效。。

用memcache扩展的情况下确实是bug，我今天也碰到了，Yii还是当前最新版本2.0.12
可能国外作者都用memcached扩展，所以没发现