diff --git a/ext/bz2/tests/gh20807.phpt b/ext/bz2/tests/gh20807.phpt
index ee3238b711b9..ed52c7085858 100644
--- a/ext/bz2/tests/gh20807.phpt
+++ b/ext/bz2/tests/gh20807.phpt
@@ -12,6 +12,12 @@ if (PHP_OS === 'FreeBSD') die('skip Worker does not handle OOM gracefully');
 if (PHP_OS_FAMILY === 'Darwin') die('skip Too slow');
 if (PHP_INT_SIZE !== 8) die('skip Only for 64-bit systems');
 if (getenv('SKIP_ASAN')) die('skip ASAN makes this test too slow');
+// The decompressed output needs more than 12 GiB of memory at its peak, which
+// takes down smaller machines (e.g. 7 GB CI runners) with the OOM killer.
+$memInfo = @file_get_contents('/proc/meminfo');
+if ($memInfo && preg_match('/MemAvailable:\s+(\d+) kB/', $memInfo, $m) && $m[1] < 13 * 1024 * 1024) {
+    die('skip Insufficient available memory (less than 13 GiB)');
+}
 ?>
 --FILE--
 <?php