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nerves_system_br
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1.34.0
1.33.9
1.33.8
1.33.7
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1.33.5
1.33.4
1.33.3
1.33.2
1.33.1
1.33.0
1.32.5
1.32.4
1.32.3
1.32.2
1.32.1
1.32.0
1.31.7
1.31.6
1.31.5
1.31.4
1.31.3
1.31.2
1.31.1
1.31.0
1.30.1
1.30.0
1.29.3
1.29.2
1.29.1
1.29.0
1.28.3
1.28.2
1.28.1
1.28.0
1.27.3
1.27.2
1.27.1
1.27.0
1.26.1
1.26.0
1.25.3
1.25.2
1.25.1
1.25.0
1.24.1
1.24.0
1.23.3
1.23.2
1.23.1
1.23.0
1.22.8
1.22.7
1.22.6
1.22.5
1.22.4
1.22.3
1.22.2
1.22.1
1.22.0
1.21.6
1.21.5
1.21.4
1.21.3
1.21.2
1.21.1
1.21.0
1.20.6
1.20.5
1.20.4
1.20.3
1.20.2
1.20.1
1.20.0
1.19.1
1.19.0
1.18.6
1.18.5
1.18.4
1.18.3
1.18.2
1.18.1
1.18.0
1.17.4
1.17.3
1.17.2
1.17.1
1.17.0
1.16.5
1.16.4
1.16.3
1.16.2
1.16.1
1.16.0
1.15.2
1.15.1
1.15.0
1.14.5
1.14.4
1.14.3
1.14.2
1.14.1
1.14.0
1.13.8
1.13.7
1.13.6
1.13.5
1.13.4
1.13.3
1.13.2
1.13.1
1.13.0
1.12.4
1.12.3
1.12.2
1.12.1
1.12.0
1.12.0-rc.0
1.11.4
1.11.3
1.11.2
1.11.1
1.11.0
1.10.3
1.10.2
1.10.1
1.10.0
1.9.5
1.9.4
1.9.3
1.9.2
1.9.1
1.9.0
1.8.6
1.8.5
1.8.4
1.8.3
1.8.2
1.8.1
1.8.0
1.7.3
1.7.2
1.7.1
1.7.0
1.6.8
1.6.7
1.6.6
1.6.5
1.6.4
1.6.3
1.6.2
1.6.1
1.6.0
1.5.6
1.5.5
1.5.4
1.5.3
1.5.2
1.5.1
1.5.0
1.4.5
1.4.4
1.4.3
1.4.2
1.4.1
1.4.0
1.3.2
1.3.1
1.3.0
1.2.2
1.2.1
1.2.0
1.1.0
1.0.1
1.0.0
1.0.0-rc.4
1.0.0-rc.3
1.0.0-rc.2
1.0.0-rc.1
1.0.0-rc.0
0.17.0
0.16.4
0.16.3
0.16.2
0.16.1-2017-11
0.16.0-2017-11
0.15.1
0.15.0
0.14.1
0.14.0
0.13.9
0.13.8
0.13.7
0.13.6
0.13.5
0.13.4
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0.13.3
0.13.2
0.13.0
0.12.1
0.12.0
0.11.1
0.11.0
0.10.1
0.10.0
0.9.4
0.9.3
0.9.2
0.9.1
0.9.0
0.8.2
0.8.1
0.8.0
0.7.0
0.6.1
0.6.0
0.5.2
0.5.1
0.5.0
0.4.2
0.4.1
Nerves System BR - Buildroot based build platform for Nerves Systems
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patches/buildroot/0017-erlang-use-available-memory-for-used-memory-calculat.patch
From 7732064ffb22f61ef0e93f3f8eec600c27766207 Mon Sep 17 00:00:00 2001
From: Frank Hunleth <fhunleth@troodon-software.com>
Date: Mon, 7 Jul 2025 14:23:04 -0400
Subject: [PATCH] erlang: use available memory for used memory calculation
---
...able-memory-on-Linux-for-used-memory.patch | 79 +++++++++++++++++++
1 file changed, 79 insertions(+)
create mode 100644 package/erlang/27.3.4.3/0002-memsup-use-available-memory-on-Linux-for-used-memory.patch
diff --git a/package/erlang/27.3.4.3/0002-memsup-use-available-memory-on-Linux-for-used-memory.patch b/package/erlang/27.3.4.3/0002-memsup-use-available-memory-on-Linux-for-used-memory.patch
new file mode 100644
index 0000000000..9922e5c58d
--- /dev/null
+++ b/package/erlang/27.3.4.3/0002-memsup-use-available-memory-on-Linux-for-used-memory.patch
@@ -0,0 +1,79 @@
+From 3ee931e8acf916653bdc329f0543d415ccdc7326 Mon Sep 17 00:00:00 2001
+From: Frank Hunleth <fhunleth@troodon-software.com>
+Date: Sat, 5 Jul 2025 21:47:29 -0400
+Subject: [PATCH] memsup: use available memory on Linux for used memory
+ calculation
+
+This updates `get_basic_mem` to improve the used memory calculation on
+Linux since the less accurate `__SC_AVPHYS_PAGES` code started being
+used.
+
+Since Linux is quick to use available DRAM as a filesystem cache, the
+`system_memory_high_watermark` alarm was getting set even though there
+was plenty of memory.
+
+Since `memsup:get_memory_data()` returns the values checked for the
+alarm, the following shows why the alarm was incorrectly set. In it, it
+shows about 222 MB out of 254 MB in use, but if you look at the
+`available_memory`, there's more like 254 MB - 114 MB = 140 MB in use.
+
+```
+> memsup:get_memory_data().
+{254287872, 222711808, {<0.3654.0>, 3819324}}
+> memsup:get_system_memory_data().
+[{available_memory,114470912},
+ {buffered_memory,139264},
+ {cached_memory,89665536},
+ {free_memory,33357824},
+ {free_swap,0},
+ {system_total_memory,254287872},
+ {total_memory,254287872},
+ {total_swap,0}]
+```
+
+With the change, the second element from `get_memory_data()` is much
+lower since it subtracts `available_memory` and the memory threshold
+isn't exceeded.
+---
+ lib/os_mon/c_src/memsup.c | 18 +++++++++---------
+ 1 file changed, 9 insertions(+), 9 deletions(-)
+
+diff --git a/lib/os_mon/c_src/memsup.c b/lib/os_mon/c_src/memsup.c
+index 2e9f337070..1e80e4beb3 100644
+--- a/lib/os_mon/c_src/memsup.c
++++ b/lib/os_mon/c_src/memsup.c
+@@ -493,15 +493,7 @@ get_extended_mem(memory_ext *me) {
+
+ static void
+ get_basic_mem(unsigned long *tot, unsigned long *used, unsigned long *pagesize){
+-#if defined(_SC_AVPHYS_PAGES) /* Does this exist on others than Solaris2? */
+- unsigned long avPhys, phys, pgSz;
+-
+- phys = sysconf(_SC_PHYS_PAGES);
+- avPhys = sysconf(_SC_AVPHYS_PAGES);
+- *used = (phys - avPhys);
+- *tot = phys;
+- *pagesize = sysconf(_SC_PAGESIZE);
+-#elif defined(__linux__) && !defined(_SC_AVPHYS_PAGES)
++#if defined(__linux__)
+ memory_ext me;
+ if (get_mem_procfs(&me) < 0) {
+ print_error("ProcFS read error");
+@@ -514,6 +506,14 @@ get_basic_mem(unsigned long *tot, unsigned long *used, unsigned long *pagesize){
+ } else {
+ *used = me.total - me.free;
+ }
++#elif defined(_SC_AVPHYS_PAGES)
++ unsigned long avPhys, phys, pgSz;
++
++ phys = sysconf(_SC_PHYS_PAGES);
++ avPhys = sysconf(_SC_AVPHYS_PAGES);
++ *used = (phys - avPhys);
++ *tot = phys;
++ *pagesize = sysconf(_SC_PAGESIZE);
+ #elif defined(BSD4_4)
+ struct vmtotal vt;
+ long pgsz;
+--
+2.43.0
+
--
2.43.0