Re: LCUP, persistent search

[Jonghyuk Choi <jongchoi@us.ibm.com>]

>The uidNumber thread got me thinking about implementing mutexes from
>application level. Using modify to atomically toggle a lock attribute
works,
>and multiple clients can wait on a lock using a persistent search to
notify
>them when it's released. However, the waiting clients would then all be
>notified at once, and thrash the server while they try to acquire the
lock.
>Is there a flag for the LCUP persistent search control to imply a
round-robin
>style of service, i.e. if multiple clients have the same search
outstanding,
>results will only be forwarded to one client at a time? Would it be worth
>suggesting?

LCUP psearch doesn't support the round-robin service.

>The other problem that this doesn't fix is, if the client currently
holding
>the lock goes away, nobody else can acquire it. If the lock attribute was
>some kind of dynamic attribute instead, you could fix that too,
automatically
>resetting it when the setting client connection closed.

another timeout scheme other than the connection timeout may be needed
to deal with ill behaving client.