- 14 May, 2020 1 commit
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Madelyn Olson authored
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- 12 May, 2020 1 commit
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antirez authored
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- 15 Oct, 2019 1 commit
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Yossi Gottlieb authored
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- 07 Oct, 2019 1 commit
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Oran Agra authored
misc: - handle SSL_has_pending by iterating though these in beforeSleep, and setting timeout of 0 to aeProcessEvents - fix issue with epoll signaling EPOLLHUP and EPOLLERR only to the write handlers. (needed to detect the rdb pipe was closed) - add key-load-delay config for testing - trim connShutdown which is no longer needed - rioFdsetWrite -> rioFdWrite - simplified since there's no longer need to write to multiple FDs - don't detect rdb child exited (don't call wait3) until we detect the pipe is closed - Cleanup bad optimization from rio.c, add another one
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- 28 Mar, 2018 1 commit
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antirez authored
While this feature is not used by Redis, ae.c implements the ability for a timer to call a finalizer callback when an timer event is deleted. This feature was bugged since the start, and because it was never used we never noticed a problem. However Anthony LaTorre was using the same library in order to implement a different system: he found a bug that he describes as follows, and which he fixed with the patch in this commit, sent me by private email: --- Anthony email --- 've found one bug in the current implementation of the timed events. It's possible to lose track of a timed event if an event is added in the finalizerProc of another event. For example, suppose you start off with three timed events 1, 2, and 3. Then the linked list looks like: 3 -> 2 -> 1 Then, you run processTimeEvents and events 2 and 3 finish, so now the list looks like: -1 -> -1 -> 2 Now, on the next iteration of processTimeEvents it starts by deleting the first event, and suppose this finalizerProc creates a new event, so that the list looks like this: 4 -> -1 -> 2 On the next iteration of the while loop, when it gets to the second event, the variable prev is still set to NULL, so that the head of the event loop after the next event will be set to 2, i.e. after deleting the next event the event loop will look like: 2 and the event with id 4 will be lost. I've attached an example program to illustrate the issue. If you run it you will see that it prints: ``` foo id = 0 spam! ``` But if you uncomment line 29 and run it again it won't print "spam!". --- End of email --- Test.c source code is as follows: #include "ae.h" #include <stdio.h> aeEventLoop *el; int foo(struct aeEventLoop *el, long long id, void *data) { printf("foo id = %lld\n", id); return AE_NOMORE; } int spam(struct aeEventLoop *el, long long id, void *data) { printf("spam!\n"); return AE_NOMORE; } void bar(struct aeEventLoop *el, void *data) { aeCreateTimeEvent(el, 0, spam, NULL, NULL); } int main(int argc, char **argv) { el = aeCreateEventLoop(100); //aeCreateTimeEvent(el, 0, foo, NULL, NULL); aeCreateTimeEvent(el, 0, foo, NULL, bar); aeMain(el); return 0; } Anthony fixed the problem by using a linked list for the list of timers, and sent me back this patch after he tested the code in production for some time. The code looks sane to me, so committing it to Redis.
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- 27 Feb, 2018 1 commit
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antirez authored
AOF fsync=always, and certain Redis Cluster bus operations, require to fsync data on disk before replying with an acknowledge. In such case, in order to implement Group Commits, we want to be sure that queries that are read in a given cycle of the event loop, are never served to clients in the same event loop iteration. This way, by using the event loop "before sleep" callback, we can fsync the information just one time before returning into the event loop for the next cycle. This is much more efficient compared to calling fsync() multiple times. Unfortunately because of a bug, this was not always guaranteed: the actual way the events are installed was the sole thing that could control. Normally this problem is hard to trigger when AOF is enabled with fsync=always, because we try to flush the output buffers to the socekt directly in the beforeSleep() function of Redis. However if the output buffers are full, we actually install a write event, and in such a case, this bug could happen. This change to ae.c modifies the event loop implementation to make this concept explicit. Write events that are registered with: AE_WRITABLE|AE_BARRIER Are guaranteed to never fire after the readable event was fired for the same file descriptor. In this way we are sure that data is persisted to disk before the client performing the operation receives an acknowledged. However note that this semantics does not provide all the guarantees that one may believe are automatically provided. Take the example of the blocking list operations in Redis. With AOF and fsync=always we could have: Client A doing: BLPOP myqueue 0 Client B doing: RPUSH myqueue a b c In this scenario, Client A will get the "a" elements immediately after the Client B RPUSH will be executed, even before the operation is persisted. However when Client B will get the acknowledge, it can be sure that "b,c" are already safe on disk inside the list. What to note here is that it cannot be assumed that Client A receiving the element is a guaranteed that the operation succeeded from the point of view of Client B. This is due to the fact that the barrier exists within the same socket, and not between different sockets. However in the case above, the element "a" was not going to be persisted regardless, so it is a pretty synthetic argument.
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- 10 Jul, 2017 1 commit
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antirez authored
In general we do not want before/after sleep() callbacks to be called when we re-enter the event loop, since those calls are only designed in order to perform operations every main iteration of the event loop, and re-entering is often just a way to incrementally serve clietns with error messages or other auxiliary operations. However, if we call the callbacks, we are then forced to think at before/after sleep callbacks as re-entrant, which is much harder without any good need. However here there was also a clear bug: beforeSleep() was actually never called when re-entering the event loop. But the new afterSleep() callback was. This is broken and in this instance re-entering afterSleep() caused a modules GIL dead lock.
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- 03 May, 2017 1 commit
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antirez authored
Instead of giving the module background operations just a small time to run in the beforeSleep() function, we can have the lock released for all the time we are blocked in the multiplexing syscall.
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- 04 Apr, 2016 1 commit
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antirez authored
This fix was suggested by Anthony LaTorre, that provided also a good test case that was used to verify the fix. The problem with the old implementation is that, the time returned by a timer event (that is the time after it want to run again) is added to the event *start time*. So if the event takes, in order to run, more than the time it says it want to be scheduled again for running, an infinite loop is triggered.
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- 28 Jun, 2013 1 commit
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antirez authored
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- 08 Nov, 2012 1 commit
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antirez authored
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- 04 Oct, 2012 1 commit
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Jokea authored
When system time changes back, the timer will not worker properly hence some core functionality of redis will stop working(e.g. replication, bgsave, etc). See issue #633 for details. The patch saves the previous time and when a system clock skew is detected, it will force expire all timers. Modiifed by @antirez: the previous time was moved into the eventLoop structure to make sure the library is still thread safe as long as you use different event loops into different threads (otherwise you need some synchronization). More comments added about the reasoning at the base of the patch, that's worth reporting here: /* If the system clock is moved to the future, and then set back to the * right value, time events may be delayed in a random way. Often this * means that scheduled operations will not be performed soon enough. * * Here we try to detect system clock skews, and force all the time * events to be processed ASAP when this happens: the idea is that * processing events earlier is less dangerous than delaying them * indefinitely, and practice suggests it is. */
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- 15 Dec, 2011 1 commit
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antirez authored
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- 21 Nov, 2011 1 commit
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antirez authored
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- 01 Jul, 2010 1 commit
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antirez authored
networking related stuff moved into networking.c moved more code more work on layout of source code SDS instantaneuos memory saving. By Pieter and Salvatore at VMware ;) cleanly compiling again after the first split, now splitting it in more C files moving more things around... work in progress split replication code splitting more Sets split Hash split replication split even more splitting more splitting minor change
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- 19 Feb, 2010 1 commit
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antirez authored
A problem with replication with multiple slaves connectiong to a single master fixed. It was due to a typo, and reported on github by the user micmac. Also the copyright year fixed from many files.
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- 28 Jan, 2010 1 commit
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antirez authored
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- 20 Jan, 2010 1 commit
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antirez authored
ae.c event loop does no longer support exception notifications, as they are fully pointless. Also a theoretical bug that never happens in practice fixed.
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- 28 Nov, 2009 1 commit
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antirez authored
ifdefs added to use kevent on Free Open and Net BSD as well. INFO and ae.c modified in order to report the multiplexing API in use
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- 23 Nov, 2009 1 commit
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antirez authored
ae.c now supports multiple polling API modules, even if only ae_select.c is implemented currently. Also adding and removing an event is now O(1).
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- 22 Mar, 2009 1 commit
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antirez authored
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