Willy Tarreau d1d005d7f6 MEDIUM: map: make the "clear map" operation yield ... As reported in issue #419, a "clear map" operation on a very large map can take a lot of time and freeze the entire process for several seconds. This patch makes sure that pat_ref_prune() can regularly yield after clearing some entries so that the rest of the process continues to work. The first part, the removal of the patterns, can take quite some time by itself in one run but it's still relatively fast. It may block for up to 100ms for 16M IP addresses in a tree typically. This change needed to declare an I/O handler for the clear operation so that we can get back to it after yielding. The second part can be much slower because it deconstructs the elements and its users, but it iterates progressively so we can yield less often here. The patch was tested with traffic in parallel sollicitating the map being released and showed no problem. Some traffic will definitely notice an incomplete map but the filling is already not atomic anyway thus this is not different. It may be backported to stable versions once sufficiently tested for side effects, at least as far as 2.0 in order to avoid the watchdog triggering when the process is frozen there. For a better behaviour, all these prune_* functions should support yielding so that the callers have a chance to continue also yield in turn.		2020-06-19 16:57:51 +02:00
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haproxy	MEDIUM: map: make the "clear map" operation yield	2020-06-19 16:57:51 +02:00
import	BUG/MEDIUM: ebtree: use a byte-per-byte memcmp() to compare memory blocks	2020-06-16 11:30:33 +02:00