I am use PhpRedis
$redis->blPop('key', 10);
How check how many process wait 'key'?
$redis->blPopCountWait('key'); => 30
Thank you!
There is no way to do that in Redis.
The closest you can get is running CLIENT LIST
and filter the reply by 'cmd=blpop', but this will not tell you the actual key(s) each connection is blocking on.