From 4f909fd37e4094c94a642b9833ea3d14fcc984e8 Mon Sep 17 00:00:00 2001
From: Vincenzo Eduardo Padulano <v.e.padulano@gmail.com>
Date: Mon, 24 Jun 2024 09:38:13 +0200
Subject: [PATCH] Prevent slowdown in yum due to high file descriptor count

Set the maximum number of file descriptors to 1024 before going through the `yum
install` step of the build, only in case `yum_requirements.txt` is present in
the recipe. This is done to mitigate a bug with old versions of rpm such as the
one shipped with the Centos7 container. See https://bugzilla.redhat.com/show_bug.cgi?id=1537564
---
 conda_smithy/templates/build_steps.sh.tmpl |  7 +++++-
 news/1958_yum_fix_ulimit.rst               | 26 ++++++++++++++++++++++
 2 files changed, 32 insertions(+), 1 deletion(-)
 create mode 100644 news/1958_yum_fix_ulimit.rst

diff --git a/conda_smithy/templates/build_steps.sh.tmpl b/conda_smithy/templates/build_steps.sh.tmpl
index 93fb76eef..46c83d8db 100644
--- a/conda_smithy/templates/build_steps.sh.tmpl
+++ b/conda_smithy/templates/build_steps.sh.tmpl
@@ -62,7 +62,12 @@ setup_conda_rc "${FEEDSTOCK_ROOT}" "${RECIPE_ROOT}" "${CONFIG_FILE}"
 {% if build_setup -%}
 {{ build_setup }}{% endif -%}
 {% if yum_build_setup is defined -%}
-{{ yum_build_setup }}{% endif -%}
+# Due to https://bugzilla.redhat.com/show_bug.cgi?id=1537564 old versions of rpm
+# are drastically slowed down when the number of file descriptors is very high.
+# This can be visible during a `yum install` step of a feedstock build.
+ulimit -n 1024
+{{ yum_build_setup }}
+{% endif -%}
 
 # make the build number clobber
 make_build_number "${FEEDSTOCK_ROOT}" "${RECIPE_ROOT}" "${CONFIG_FILE}"
diff --git a/news/1958_yum_fix_ulimit.rst b/news/1958_yum_fix_ulimit.rst
new file mode 100644
index 000000000..edb556f2e
--- /dev/null
+++ b/news/1958_yum_fix_ulimit.rst
@@ -0,0 +1,26 @@
+**Added:**
+
+* <news item>
+
+**Changed:**
+
+* Changed the build_steps.sh template so that it sets the number of maximum file
+  descriptors to 1024. This is done to mitigate a bug in old rpm versions (such
+  as the one shipped with the Centos7 container) that cause the yum install step
+  to take tremendously longer than necessary. See https://bugzilla.redhat.com/show_bug.cgi?id=1537564
+
+**Deprecated:**
+
+* <news item>
+
+**Removed:**
+
+* <news item>
+
+**Fixed:**
+
+* <news item>
+
+**Security:**
+
+* <news item>