diff --git a/man5/proc.5 b/man5/proc.5
index d487e2eac..a106b1797 100644
--- a/man5/proc.5
+++ b/man5/proc.5
@@ -3219,6 +3219,9 @@ file is also nonzero, then the machine will be rebooted.
 .IR /proc/sys/kernel/pid_max " (since Linux 2.5.34)"
 This file specifies the value at which PIDs wrap around
 (i.e., the value in this file is one greater than the maximum PID).
+PIDs greater than this value not allocated;
+thus, the value in this file also acts as a system-wide limit
+on the total number of processes and threads.
 The default value for this file, 32768,
 results in the same range of PIDs as on earlier kernels.
 On 32-bit platforms, 32768 is the maximum value for