On 1/03/2016 6:46 a.m., Alex Rousskov wrote: > On 02/29/2016 10:22 AM, Marcus Kool wrote: >> >>> * Choices. >>> >>> Overall, there are three options for handling an impossible situation: >>> >>> 1. Quit Squid process. This is what Squid does today in most cases. >>> When the impossible happens, you get a crash. Very predictable. >>> No malformed/corrupted/misleading HTTP messages (some are truncated). >>> No memory leaks. >>> >>> 2. Quit the current processing sequence but keep Squid process running, >>> assuming that [most] other processing sequences are not affected. >>> [If you are familiar with programming, this is done by throwing >>> exceptions instead of asserting and catching those exceptions at >>> "processing sequence" boundaries]. >>> >>> 3. Keep executing the current processing sequence, assuming that the >>> assertion was wrong or unimportant. This is what you might be >>> suggesting above. When the impossible happens, you may get a crash, >>> memory leaks, malformed/corrupted/misleading HTTP messages, or normal >>> behavior, depending on the assertion and traffic. >>> >>> IMO, we should make #2 the default, but make the choice between all >>> three options configurable by the admin (without recompiling Squid). > > >> Let me suggest #4 : >> >> immediately execute an external program that calls gdb or any other >> debugger >> which produces a stack trace of all squid processes and then do #1 or #2. > > This is not really #4. It is an enhancement for any of the three > options. IIRC, Squid even supported gdb stack tracing natively on some > platforms (but a script would arguably be better, except for busy > proxies that cannot be blocked for 2-4 seconds it takes to run that script). > This already exists. Squid does it *right now*. You never received a "The Squid Cache (version %s) died." email ? When mail [1] is working on the proxy Squid will use it to send an email to the configured administrator email address [2], root@ address for the proxies private hostname [3], or root@ address for the proxies public hostname [4] - in that order or preference. - Of course, far too many people dont use FQDN for those config settings... [1] http://www.squid-cache.org/Doc/config/mail_program/ [2] http://www.squid-cache.org/Doc/config/mail_from/ [3] http://www.squid-cache.org/Doc/config/unique_hostname/ [4] http://www.squid-cache.org/Doc/config/visible_hostname/ > >> The stack dumps will be save in an assertion failure log file which admins >> can send to Squid developers. >> If Squid is also built with --enable-stacktraces a stack trace will be recorded in cache.log after FATAL messages. - Of course. Speed at any cost "needs" prohibit doing anything that might slow down the Squid restart process. So that gets disabled. Amos _______________________________________________ squid-users mailing list squid-users@xxxxxxxxxxxxxxxxxxxxx http://lists.squid-cache.org/listinfo/squid-users
