From 5ce3d0d8e57c90f51090a052390765d76c844d6f Mon Sep 17 00:00:00 2001 From: Thomas Stuefe Date: Tue, 2 Jun 2020 21:04:13 +0200 Subject: [PATCH] 8245707: Increase Metaspace reserve alignment Reviewed-by: iklam, coleenp --- src/hotspot/share/memory/metaspace.cpp | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/src/hotspot/share/memory/metaspace.cpp b/src/hotspot/share/memory/metaspace.cpp index 583f52d41f4..f43fc99a6ad 100644 --- a/src/hotspot/share/memory/metaspace.cpp +++ b/src/hotspot/share/memory/metaspace.cpp @@ -1077,6 +1077,13 @@ void Metaspace::ergo_initialize() { _commit_alignment = page_size; _reserve_alignment = MAX2(page_size, (size_t)os::vm_allocation_granularity()); + // The upcoming Metaspace rewrite will impose a higher alignment granularity. + // To prepare for that and to catch/prevent any misuse of Metaspace alignment + // which may creep in, up the alignment a bit. + if (_reserve_alignment == 4 * K) { + _reserve_alignment *= 4; + } + // Do not use FLAG_SET_ERGO to update MaxMetaspaceSize, since this will // override if MaxMetaspaceSize was set on the command line or not. // This information is needed later to conform to the specification of the