Reduce/less disk seek patch for daemontools-0.76 ( delays the scanning interval to 15sec (default is 5sec) - can change with 'export SVSCAN_INTERVAL_SEC=nnn'), suitable for developer's machine!)

less-diskseek.diff

Index: daemontools-0.76/src/supervise.c
===================================================================
RCS file: /home/shirai/root/cvs/project/other/daemontools/daemontools-0.76/src/supervise.c,v
retrieving revision 1.1.1.1
retrieving revision 1.4
diff -u -r1.1.1.1 -r1.4
--- daemontools-0.76/src/supervise.c	16 Dec 2001 02:54:52 -0000	1.1.1.1
+++ daemontools-0.76/src/supervise.c	30 May 2002 07:33:07 -0000	1.4
@@ -15,6 +15,10 @@
 #include "iopause.h"
 #include "taia.h"
 #include "deepsleep.h"
+#include "scan.h"
+
+#define IOPAUSE_TIMEOUT_ENV "SUPERVISE_MONITOR_MSEC"
+#define IOPAUSE_TIMEOUT_DEFAULT 30000
 
 #define FATAL "supervise: fatal: "
 #define WARNING "supervise: warning: "
@@ -34,6 +38,8 @@
 
 char status[18];
 
+int iopause_timeout = IOPAUSE_TIMEOUT_DEFAULT;
+
 void pidchange(void)
 {
   struct taia now;
@@ -130,7 +136,7 @@
     x[1].fd = fdcontrol;
     x[1].events = IOPAUSE_READ;
     taia_now(&stamp);
-    taia_uint(&deadline,3600);
+    taia_uint(&deadline, iopause_timeout);
     taia_add(&deadline,&stamp,&deadline);
     iopause(x,2,&deadline,&stamp);
 
@@ -205,6 +211,17 @@
   }
 }
 
+/* terminate supervised program on SIGTERM. */
+void on_sig_term(void)
+{
+  flagwant = 1;
+  flagwantup = 0;
+  if (pid) { kill(pid,SIGTERM); kill(pid,SIGCONT); flagpaused = 0; }
+  announce();
+  flagexit = 1;
+  announce();
+}
+
 int main(int argc,char **argv)
 {
   struct stat st;
@@ -213,6 +230,15 @@
   if (!dir || argv[2])
     strerr_die1x(100,"supervise: usage: supervise dir");
 
+  {
+    char * iopause_timeout_env = env_get(IOPAUSE_TIMEOUT_ENV);
+    if (iopause_timeout_env) {
+      unsigned long msec;
+      scan_ulong(iopause_timeout_env, &msec);
+      iopause_timeout = (int)msec;
+    }
+  }
+
   if (pipe(selfpipe) == -1)
     strerr_die4sys(111,FATAL,"unable to create pipe for ",dir,": ");
   coe(selfpipe[0]);
@@ -222,6 +248,8 @@
 
   sig_block(sig_child);
   sig_catch(sig_child,trigger);
+
+  sig_catch(sig_term, on_sig_term);
 
   if (chdir(dir) == -1)
     strerr_die4sys(111,FATAL,"unable to chdir to ",dir,": ");
Index: daemontools-0.76/src/svscan.c
===================================================================
RCS file: /home/shirai/root/cvs/project/other/daemontools/daemontools-0.76/src/svscan.c,v
retrieving revision 1.1.1.1
retrieving revision 1.4
diff -u -r1.1.1.1 -r1.4
--- daemontools-0.76/src/svscan.c	16 Dec 2001 02:54:52 -0000	1.1.1.1
+++ daemontools-0.76/src/svscan.c	30 May 2002 07:34:04 -0000	1.4
@@ -1,6 +1,7 @@
 #include <unistd.h>
 #include <sys/types.h>
 #include <sys/stat.h>
+#include <signal.h>
 #include "direntry.h"
 #include "strerr.h"
 #include "error.h"
@@ -8,12 +9,17 @@
 #include "coe.h"
 #include "fd.h"
 #include "env.h"
+#include "sig.h"
 #include "str.h"
 #include "byte.h"
 #include "pathexec.h"
+#include "scan.h"
 
 #define SERVICES 1000
 
+#define SCAN_INTERVAL_ENV "SVSCAN_INTERVAL_SEC"
+#define SCAN_INTERVAL_DEFAULT 15
+
 #define WARNING "svscan: warning: "
 #define FATAL "svscan: fatal: "
 
@@ -190,14 +196,42 @@
   }
 }
 
+/* terminate each supervise on SIGTERM. */
+void on_sig_term(void)
+{
+  int i;
+  for (i = 0; i < numx; ++i) {
+    if (x[i].pid) {
+      kill(x[i].pid, SIGTERM);
+    }
+    if (x[i].pidlog) {
+      kill(x[i].pidlog, SIGTERM);
+    }
+  }
+  _exit(0);
+}
+
 int main(int argc,char **argv)
 {
+  unsigned long scan_interval;
+
   if (argv[0] && argv[1])
     if (chdir(argv[1]) == -1)
       strerr_die4sys(111,FATAL,"unable to chdir to ",argv[1],": ");
 
+  {
+    char * scan_interval_env = env_get(SCAN_INTERVAL_ENV);
+    if (scan_interval_env) {
+      scan_ulong(scan_interval_env, &scan_interval);
+    } else {
+      scan_interval = SCAN_INTERVAL_DEFAULT;
+    }
+  }
+
+  sig_catch(sig_term, on_sig_term);
+
   for (;;) {
     doit();
-    sleep(5);
+    sleep(scan_interval);
   }
 }