mirror of
git://gcc.gnu.org/git/gcc.git
synced 2024-12-21 08:03:41 +08:00
38 lines
1.6 KiB
Plaintext
38 lines
1.6 KiB
Plaintext
|
Performance of the incremental collector can be greatly enhanced with
|
||
|
-DNO_EXECUTE_PERMISSION.
|
||
|
|
||
|
The collector should run with all of the -32, -n32 and -64 ABIs. Remember to
|
||
|
define the AS macro in the Makefile to be "as -64", or "as -n32".
|
||
|
|
||
|
If you use -DREDIRECT_MALLOC=GC_malloc with C++ code, your code should make
|
||
|
at least one explicit call to malloc instead of new to ensure that the proper
|
||
|
version of malloc is linked in.
|
||
|
|
||
|
Sproc threads are not supported in this version, though there may exist other
|
||
|
ports.
|
||
|
|
||
|
Pthreads support is provided. This requires that:
|
||
|
|
||
|
1) You compile the collector with -DIRIX_THREADS specified in the Makefile.
|
||
|
|
||
|
2) You have the latest pthreads patches installed.
|
||
|
|
||
|
(Though the collector makes only documented pthread calls,
|
||
|
it relies on signal/threads interactions working just right in ways
|
||
|
that are not required by the standard. It is unlikely that this code
|
||
|
will run on other pthreads platforms. But please tell me if it does.)
|
||
|
|
||
|
3) Every file that makes thread calls should define IRIX_THREADS and then
|
||
|
include gc.h. Gc.h redefines some of the pthread primitives as macros which
|
||
|
also provide the collector with information it requires.
|
||
|
|
||
|
4) pthread_cond_wait and pthread_cond_timed_wait should be prepared for
|
||
|
premature wakeups. (I believe the pthreads and realted standards require this
|
||
|
anyway. Irix pthreads often terminate a wait if a signal arrives.
|
||
|
The garbage collector uses signals to stop threads.)
|
||
|
|
||
|
5) It is expensive to stop a thread waiting in IO at the time the request is
|
||
|
initiated. Applications with many such threads may not exhibit acceptable
|
||
|
performance with the collector. (Increasing the heap size may help.)
|
||
|
|