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8303215: Make thread stacks not use huge pages

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Reviewed-by: stuefe, dholmes
This commit is contained in:
Poonam Bajaj 2023-06-02 13:32:22 +00:00
parent cb1e5e3f0f
commit 59d9d9fcb9
2 changed files with 26 additions and 8 deletions
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20
src/hotspot/os/linux/os_linux.cpp
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@ -927,6 +927,15 @@ bool os::create_thread(Thread* thread, ThreadType thr_type,
}
assert(is_aligned(stack_size, os::vm_page_size()), "stack_size not aligned");
// Add an additional page to the stack size to reduce its chances of getting large page aligned
// so that the stack does not get backed by a transparent huge page.
size_t default_large_page_size = os::Linux::default_large_page_size();
if (default_large_page_size != 0 &&
stack_size >= default_large_page_size &&
is_aligned(stack_size, default_large_page_size)) {
stack_size += os::vm_page_size();
}
int status = pthread_attr_setstacksize(&attr, stack_size);
if (status != 0) {
// pthread_attr_setstacksize() function can fail
@ -3745,8 +3754,11 @@ bool os::Linux::setup_large_page_type(size_t page_size) {
}
void os::large_page_init() {
// 1) Handle the case where we do not want to use huge pages and hence
// there is no need to scan the OS for related info
// Always initialize the default large page size even if large pages are not being used.
size_t default_large_page_size = scan_default_large_page_size();
os::Linux::_default_large_page_size = default_large_page_size;
// 1) Handle the case where we do not want to use huge pages
if (!UseLargePages &&
!UseTransparentHugePages &&
!UseHugeTLBFS &&
@ -3764,9 +3776,7 @@ void os::large_page_init() {
return;
}
// 2) Scan OS info
size_t default_large_page_size = scan_default_large_page_size();
os::Linux::_default_large_page_size = default_large_page_size;
// 2) check if large pages are configured
if (default_large_page_size == 0) {
// No large pages configured, return.
warn_no_large_pages_configured();

14
src/hotspot/os_cpu/linux_aarch64/globals_linux_aarch64.hpp
View File

@ -30,10 +30,18 @@
// (see globals.hpp)
define_pd_global(bool, DontYieldALot, false);
define_pd_global(intx, ThreadStackSize, 2048); // 0 => use system default
define_pd_global(intx, VMThreadStackSize, 2048);
define_pd_global(intx, CompilerThreadStackSize, 2048);
// Set default stack sizes < 2MB so as to prevent stacks from getting
// large-page aligned and backed by THPs on systems where 2MB is the
// default huge page size. For non-JavaThreads, glibc may add an additional
// guard page to the total stack size, so to keep the default sizes same
// for all the following flags, we set them to 2 pages less than 2MB. On
// systems where 2MB is the default large page size, 4KB is most commonly
// the regular page size.
define_pd_global(intx, ThreadStackSize, 2040); // 0 => use system default
define_pd_global(intx, VMThreadStackSize, 2040);
define_pd_global(intx, CompilerThreadStackSize, 2040);
define_pd_global(uintx,JVMInvokeMethodSlack, 8192);