File 3651-erts-Adjust-binary-growth-to-be-10.patch of Package erlang

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File 3651-erts-Adjust-binary-growth-to-be-10.patch of Package erlang (Revision 84136f040b8e10a77a20fc548a9bd409)

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From b3e930b5008248673cb4eb374e61afb464bb2159 Mon Sep 17 00:00:00 2001
From: Lukas Larsson <lukas@erlang.org>
Date: Fri, 30 Apr 2021 11:45:44 +0200
Subject: [PATCH 1/2] erts: Adjust binary growth to be 10%

When a refc binary is very large, it does not make sense
to double the size of it anymore when preallocating for
more writes. So when it is larger than 64 MB we just
increase it with 10%.
---
 erts/emulator/beam/erl_bits.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/erts/emulator/beam/erl_bits.c b/erts/emulator/beam/erl_bits.c
index 2990f4e775..d332e35499 100644
--- a/erts/emulator/beam/erl_bits.c
+++ b/erts/emulator/beam/erl_bits.c
@@ -55,6 +55,11 @@ typedef Uint16 erlfp16;
 
 static byte get_bit(byte b, size_t a_offs); 
 
+/* If the proc bin is larger than 16 MB,
+   we only increase by 20% instead of doubling */
+#define GROW_PROC_BIN_SIZE(size) \
+    (((size) > (1ull << 24)) ? 1.2*(size) : 2*(size))
+
 #if defined(ERTS_SMP)
 /* the state resides in the current process' scheduler data */
 #elif defined(ERL_BITS_REENTRANT)
@@ -1348,7 +1353,8 @@ erts_bs_append(Process* c_p, Eterm* reg, Uint live, Eterm build_size_term,
      */
     binp = pb->val;
     if (binp->orig_size < pb->size) {
-	Uint new_size = 2*pb->size;
+	Uint new_size = GROW_PROC_BIN_SIZE(pb->size);
+
 	binp = erts_bin_realloc(binp, new_size);
 	pb->val = binp;
 	pb->bytes = (byte *) binp->orig_bytes;
@@ -1426,7 +1432,7 @@ erts_bs_append(Process* c_p, Eterm* reg, Uint live, Eterm build_size_term,
 	}
 	used_size_in_bits = erts_bin_offset + build_size_in_bits;
 	used_size_in_bytes = NBYTES(used_size_in_bits);
-	bin_size = 2*used_size_in_bytes;
+	bin_size = GROW_PROC_BIN_SIZE(used_size_in_bytes);
 	bin_size = (bin_size < 256) ? 256 : bin_size;
 
 	/*
@@ -1535,7 +1541,7 @@ erts_bs_private_append(Process* p, Eterm bin, Eterm build_size_term, Uint unit)
      */
     binp = pb->val;
     if (binp->orig_size < pb->size) {
-	Uint new_size = 2*pb->size;
+	Uint new_size = GROW_PROC_BIN_SIZE(pb->size);
 
 	if (pb->flags & PB_IS_WRITABLE) {
 	    /*
-- 
2.31.1

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File 3651-erts-Adjust-binary-growth-to-be-10.patch of Package erlang (Revision 84136f040b8e10a77a20fc548a9bd409)

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