general/4914: scoreboard connection count (conn_count) too small in some cases

[Anatole Shaw <as...@bigwords.com>]

>Number:         4914
>Category:       general
>Synopsis:       scoreboard connection count (conn_count) too small in some cases
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Thu Aug 26 19:40:04 PDT 1999
>Last-Modified:
>Originator:     ash+apache@bigwords.com
>Organization:
apache
>Release:        1.3.9
>Environment:
FreeBSD/i386 3.2-STABLE
GCC 2.7.2.3

$ uname -a
FreeBSD ui1 3.2-STABLE FreeBSD 3.2-STABLE #0: Tue Aug 24 08:56:26 PDT 1999     ash@ui1:/usr/src/sys/compile/BIGUI  i386
>Description:
The scoreboard connection count (conn_count) is an 'unsigned short int',
which generally translates to 8 bits, i.e., a range of 0..255.
This is fine when HARD_SERVER_LIMIT is left at the default of 256,
but necessarily causes some problems when it and MaxClients are larger.
>How-To-Repeat:
Raise HARD_SERVER_LIMIT and MaxClients above 256, and give Apache some
appropriate traffic with ab.  Pour small glass of Cognac.  Enjoy.
The problem is nicely evident when looking at the server status report.
>Fix:
--- include/scoreboard.h.orig   Tue Apr 27 13:36:29 1999
+++ include/scoreboard.h        Thu Aug 26 11:21:10 1999
@@ -141,7 +141,7 @@
     unsigned long my_access_count;
     unsigned long my_bytes_served;
     unsigned long conn_bytes;
-    unsigned short conn_count;
+    unsigned long conn_count;
 #if defined(NO_GETTIMEOFDAY)
     clock_t start_time;
     clock_t stop_time;

--- main/http_main.c.orig       Tue Aug 10 06:54:48 1999
+++ main/http_main.c    Thu Aug 26 11:22:40 1999
@@ -2145,7 +2145,7 @@
                ss->my_access_count = 0L;
                ss->my_bytes_served = 0L;
            }
-           ss->conn_count = (unsigned short) 0;
+           ss->conn_count = (unsigned long) 0;
            ss->conn_bytes = (unsigned long) 0;
        }
        if (r) {

--- modules/standard/mod_status.c.orig  Sat Jun  5 08:48:12 1999
+++ modules/standard/mod_status.c       Thu Aug 26 11:21:57 1999
@@ -236,7 +236,7 @@
     unsigned long count = 0;
     unsigned long lres, bytes;
     unsigned long my_lres, my_bytes, conn_bytes;
-    unsigned short conn_lres;
+    unsigned long conn_lres;
     unsigned long bcount = 0;
     unsigned long kbcount = 0;
     long req_time;
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