> What kinds of operations are protected by read locks? Looking at almost any of the global data structures, such as error tables, OID tables, and so on.
>Often, RW locks aren't a win because maintaining just the read locks (without >any writers) introduces contention at the hardware level, and parallelism does >not increase all that much as a result. Paul McKenney's dissertation on RCU >has some examples. We've monitored one of our applications, an SSL-terminating HTTP proxy server, under load. Of all the mutexes (futex, actually) in the system, the "error" lock is the most highly contended one. I'll see about posting some statistics. /r$ -- Principal Security Engineer Akamai Technologies, Cambridge, MA IM: rs...@jabber.me; Twitter: RichSalz :��I"Ϯ��r�m���� (����Z+�7�zZ)���1���x��h����W^��^��%�� ��&jם.+-1�ځ��j:+v�������h�