Description:
------------
Two related descriptions.

1. On heavy loaded server (20-40 requests/s) I periodically (once a second) get an error message from memcached extension:

# tail -f php-error_log |grep failed
PHP Notice:  Memcache::get(): marked server '127.0.0.1:11211' as failed
...

But the server is up, the maximum number of connections (-m 1024) is not reached. And this error does not depend on how long the memcached server is running: a couple of minutes after memcached restart I can watch the same error, the statistics is:

stats
STAT pid 19854
STAT uptime 337
STAT time 1181115051
STAT version 1.2.2
STAT pointer_size 64
STAT rusage_user 1.727737
STAT rusage_system 6.867955
STAT curr_items 63413
STAT total_items 64222
STAT bytes 114838739
STAT curr_connections 16
STAT total_connections 3888
STAT connection_structures 27
STAT cmd_get 259618
STAT cmd_set 64563
STAT get_hits 196161
STAT get_misses 63457
STAT evictions 0
STAT bytes_read 148496793
STAT bytes_written 394115419
STAT limit_maxbytes 1073741824
STAT threads 1

I tried to disable setCompressThreshold, increase memcache.chunk_size,
disable persistent connections, enlarge timeout parameters, but an error
still happens. Furthermore, this error happens on Windows more
frequently, even without heavy load, but I cannot reproduce.

I have the only memcached server added:

$this->connection = new Memcache(); 
$this->connection->addServer(
    "localhost", 
    11211,
    true,
    1,
    10, 
    2
);

2. Seems in some cases I could reproduce this bug: if the key length is wuite large (in my situation - 361 bytes), "marked server '127.0.0.1:11211' as failed" is always reproducible. And this message is generated not immediately, but after the timeout (10 seconds in the example above) - very strange behaviour.