ensiferum · HackerTrans

vor 6 Jahrendiscuss

Interested to know what is the size of the project? I'm currently working on something small about 60kloc of my code, another 60k in third_party and Qt5 as additional dep. There are a few hiccups every now and then when the Clion UI freezes for a few seconds but other than that it's been working really great.

ensiferum

vor 6 Jahrendiscuss

I recommend Clion. It simply just works.

ensiferum

vor 7 Jahrendiscuss

Yes, it's an imperfect world and you can't control what happens in a library but the attitude "it doesn't matter if my code is messed up or not, some library will still do the wrong thing" doesn't help. All you can do is make your code work properly and that's what you (and everyone else) should do.

Again it's imperfect world saying that "it won't work because x, y, z will happen" is not the right attitude and is bad attitude. Most of your code should treat it as just a resource allocation failure and in a sane program that is indicated by propagating an exception up the stack. Now you might be right that the program might fail when it'd be the time to display a message box to the user or whatever. But somewhere in the middle layers of the code you don't have that context, you don't know that it will fail. Therefore that part of your code really should be (exception) neutral just like in any resource allocation case.

ensiferum

vor 7 Jahrendiscuss

You're right the memory allocator ultimately gets the memory it manages from the OS but as a programmer you're looking at it from the abstraction that its API provides and assuming any particular condition that would cause a NULL to be returned or bad_alloc to be thrown may or may not be correct.

The other point is that there's a distinction between kernele's view of OOM condition and some memory managers's OOM condition. Consider you run two processes, both allocate X gigs of memory and both succeed. However once you start running and committing the memory you'll get a kernel OOM condition and one process is killed. This is the overcomitting you mentioned.

Personally I don't see why people make such a big fuzz about dealing with memory allocation failures. Memory is just a resource same as any other OS resource, socket, mutex, pipe whatever. Normally in a well designed application you throw on these conditions and unwind your stack and ultimately report the error to the user or print it to the log and perhaps try again later. Just because it's "memory" should not make it special IMHO.

ensiferum

vor 7 Jahrendiscuss

In general, the out of memory condition doesn't always come from the Linux kernel however but from the underlying memory allocator which typically is the memory allocator in the CRT in libc. Just because some process's memory allocator returned NULL or threw bad_alloc doesn't mean the system as whole is running out of memory.

When the kernel is running out of memory it will just start the OOM killer which will kill a process with low "nice" value.

ensiferum

vor 9 Jahrendiscuss

But does it have swear words??

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