On Tuesday, 29 January 2013 at 15:43:00 UTC, n00b wrote:
If I do the following... :
foreach(string foo ; bigFilesList)
{
string file = cast(string)std.file.read(foo);
}
...I run out of memory because the garbage collector apparently
does not free previously loaded files, even though there isn't
any reference left to them. ( I'm using D2.59, later versions
do not seem to work with visualD )
Is it a bug?
AFAIK, this is a limitation for win32, where the GC mistakes
random bit patterns for pointers, and then refuses to release the
memory.
If I'm not mistaken, the "classic" workaround is to manually
allocate (using the GC), but telling it to not scan. This way,
you still have a safelly GC allocated array, but it gets
correctly collected:
http://dlang.org/phobos/core_memory.html
//----
//Original string
string file = cast(string)std.file.read(foo);
//allocate new string
immutable len = file.length;
void* p = GC.malloc(file.length, GC.BlkAttr.NO_SCAN);
char[] newString = (cast(char*)p) [0 .. len];
//Copy string
newString[] = file[];
//release old string
GC.free(cast(void*)file.ptr);
//place new string into old
file = cast(string) newString;
//----
Note that if you don't need "file" at the end of the loop, you
can just explicitly release file and move on, rather than do all
that.
...
I think.
