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Sure it will mess up some things, but when management is pushing to limit the downtime of, for instance, a golden-image provisioned Linux machine, I'd kill it off no problem.
Now when we are talking a hardware box running some form of Oracle/mySQL - no, don't use -9 indeed.
As if often the case with stackoverflow answers, all of them are wrong in different ways. You should only kill -9 when every other signal the program is likely to respond to has not worked. kill -9 is likely to leave program in a state that requires manual intervention, especially if that program is a database. If you're a developer, before you kill -9 a program send SIGTERM (ie kill without args or kill -15). If the…
You can't really corrupt a database that easily, can you? That's half the point of using a database, so you have transactions, etc.
I think it was Oracle.
If I remember correctly we had to get the vendor involved
This happened after an unclean shutdown (power failure). The disk were RAID, but the cache battery was dead so there was some corrupt data written to the disk on block level.
THis could happen too on a kill -9.
As if often the case with stackoverflow answers, all of them are wrong in different ways. You should only kill -9 when every other signal the program is likely to respond to has not worked. kill -9 is likely to leave program in a state that requires manual intervention, especially if that program is a database. If you're a developer, before you kill -9 a program send SIGTERM (ie kill without args or kill -15). If the…
As a useful variant of this: I have grown accustomed to killing processes that hang with kill -11 (SIGSEGV). This is essentially the same as -9, with the exception that it creates a coredump. Saves a lot of hassle with manually attaching GDB.
~ The most interesting man in the world.
As if often the case with stackoverflow answers, all of them are wrong in different ways. You should only kill -9 when every other signal the program is likely to respond to has not worked. kill -9 is likely to leave program in a state that requires manual intervention, especially if that program is a database. If you're a developer, before you kill -9 a program send SIGTERM (ie kill without args or kill -15). If the…
If a database is not kill -9 resistant then how can it be power-off resistant?
Earlier quoted context omitted.
As a useful variant of this: I have grown accustomed to killing processes that hang with kill -11 (SIGSEGV). This is essentially the same as -9, with the exception that it creates a coredump. Saves a lot of hassle with manually attaching GDB.
Yup, there are risks too though with that approach. You should be sure that ulimit for core size is large enough (not default almost always). Also, a core dump can take a very long time if your programs address space is large. It might involve writing tens of gigabytes to disk. So not only do you need the file system space, but you also need to be prepared to wait tens of minutes while your program is dumping core.
Fiber optic cables are dug up by backhoes. Hard drives randomly fail. RAM is corrupted by cosmic rays. Racks lose power. CPU fans stop spinning. If your process relies on not being kill -9'd, then you might as well quit programming and go buy a lottery ticket.
Fiber optic cables are dug up by backhoes. Hard drives randomly fail. RAM is corrupted by cosmic rays. Racks lose power. CPU fans stop spinning. If your process relies on not being kill -9'd, then you might as well quit programming and go buy a lottery ticket.
This is a bit like saying that since your car can do emergency braking, you should always do emergency braking. Some processes clean up after themselves more neatly, or finish the current run of what they're doing first. It's dependent on what it is that you're stopping.
I do it all the time. In production. While testing my code. ~ The most interesting man in the world.