Add "prealloc" variable to configure script

sar (or sadc) allocates empty records in the data files it creates so
that it can save statistics for devices (disks, network interfaces,
etc.) that may be added to the system after the file was created.
The drawback is that data files take more space on disk than actually
strictly necessary.
Using the "prealloc" variable with configure (before compiling sysstat),
the user can tell how much space he wants to allocate.
This variable will determine the size of data files created by sar/sadc.
The default value is 1, meaning that some empty records will be
allocated.
A value of 0 means that data files will be the smallest possible.

.gitignore

@@ -8,6 +8,7 @@ sysstat
 crontab
 version.h
 sysconfig.h
+prealloc.h
 sysstat.sysconfig
 sysstat.service
 sysstat.crond

Makefile.in

@@ -199,7 +199,7 @@ xml_stats.o: xml_stats.c sa.h sadf.h ioconf.h sysconfig.h xml_stats.h
 
 json_stats.o: json_stats.c sa.h sadf.h ioconf.h sysconfig.h json_stats.h
 
-sa_wrap.o: sa_wrap.c sa.h rd_stats.h count.h rd_sensors.h
+sa_wrap.o: sa_wrap.c sa.h rd_stats.h count.h rd_sensors.h prealloc.h
 
 format.o: format.c sadf.h
 
@@ -506,7 +506,7 @@ clean:
 	find nls -name "*.gmo" -exec rm -f {} \;
 
 almost-distclean: clean nls/sysstat.pot
-	rm -f sa1 sa2 sysstat cron/crontab version.h sysconfig.h
+	rm -f sa1 sa2 sysstat cron/crontab version.h sysconfig.h prealloc.h
 	rm -f sysstat.sysconfig cron/sysstat.crond cron/sysstat.cron.daily sysstat.service
 	rm -f cron/sysstat.cron.hourly cron/sysstat.crond.sample cron/sysstat.crond.sample.in
 	rm -f contrib/isag/isag

build/prealloc

@@ -0,0 +1,12 @@
+
+sar (or sadc) allocates empty records in the data files it creates so that
+it can save statistics for devices (disks, network interfaces, etc.) that
+may be added to the system after the file was created. The drawback is that
+data files take more space on disk than actually strictly necessary.
+Answer here a positive integer number telling sar/sadc how much space they
+should allocate for such devices. The default value (1) means that a few
+records will be allocated. A greater value (e.g. 2 or 3) means that many
+more of them will be allocated. A value of 0 doesn't allocate any empty
+records.
+The default value should be OK for most of you.
+

configure

@@ -642,6 +642,8 @@ COMPRESS_MANPG
 IGNORE_MAN_GROUP
 MAN_GROUP
 man_group
+PREALLOC_FACTOR
+prealloc
 COMPRESSAFTER
 compressafter
 HISTORY
@@ -758,6 +760,7 @@ sa_dir
 conf_dir
 history
 compressafter
+prealloc
 man_group
 cron_owner
 cron_interval'
@@ -1407,6 +1410,8 @@ Some influential environment variables:
   compressafter
               number of days after which data files are compressed (default
               value is 10)
+  prealloc    preallocation factor that will determine data files size
+              (default value is 1)
   man_group   group for manual pages
   cron_owner  crontab owner
   cron_interval
@@ -5053,6 +5058,19 @@ fi
 $as_echo "$COMPRESSAFTER" >&6; }
 
 
+# Preallocation factor
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking preallocation factor value" >&5
+$as_echo_n "checking preallocation factor value... " >&6; }
+
+if test x$prealloc = x""; then
+   PREALLOC_FACTOR=1
+else
+   PREALLOC_FACTOR=$prealloc
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $PREALLOC_FACTOR" >&5
+$as_echo "$PREALLOC_FACTOR" >&6; }
+
+
 # Manual page group
 grep ^man: /etc/group >/dev/null 2>&1
 if test $? = 0; then
@@ -5360,6 +5378,8 @@ ac_config_files="$ac_config_files version.h:version.in"
 		# File must be renamed
 ac_config_files="$ac_config_files sysconfig.h:sysconfig.in"
 	# File must be renamed
+ac_config_files="$ac_config_files prealloc.h:prealloc.in"
+	# File must be renamed
 ac_config_files="$ac_config_files cron/sysstat.cron.daily"
 
 ac_config_files="$ac_config_files cron/sysstat.cron.hourly"
@@ -6106,6 +6126,7 @@ do
     "sysstat.sysconfig") CONFIG_FILES="$CONFIG_FILES sysstat.sysconfig" ;;
     "version.h") CONFIG_FILES="$CONFIG_FILES version.h:version.in" ;;
     "sysconfig.h") CONFIG_FILES="$CONFIG_FILES sysconfig.h:sysconfig.in" ;;
+    "prealloc.h") CONFIG_FILES="$CONFIG_FILES prealloc.h:prealloc.in" ;;
     "cron/sysstat.cron.daily") CONFIG_FILES="$CONFIG_FILES cron/sysstat.cron.daily" ;;
     "cron/sysstat.cron.hourly") CONFIG_FILES="$CONFIG_FILES cron/sysstat.cron.hourly" ;;
     "cron/sysstat.crond") CONFIG_FILES="$CONFIG_FILES cron/sysstat.crond" ;;

configure.in

@@ -318,6 +318,17 @@ fi
 AC_MSG_RESULT($COMPRESSAFTER)
 AC_SUBST(COMPRESSAFTER)
 
+# Preallocation factor
+AC_MSG_CHECKING(preallocation factor value)
+AC_ARG_VAR([prealloc],[preallocation factor that will determine data files size (default value is 1)])
+if test x$prealloc = x""; then
+   PREALLOC_FACTOR=1
+else
+   PREALLOC_FACTOR=$prealloc
+fi
+AC_MSG_RESULT($PREALLOC_FACTOR)
+AC_SUBST(PREALLOC_FACTOR)
+
 # Manual page group
 grep ^man: /etc/group >/dev/null 2>&1
 if test $? = 0; then
@@ -566,6 +577,7 @@ AC_CONFIG_FILES([cron/crontab:cron/crontab.sample])	# File must be renamed
 AC_CONFIG_FILES([sysstat.sysconfig])
 AC_CONFIG_FILES([version.h:version.in])		# File must be renamed
 AC_CONFIG_FILES([sysconfig.h:sysconfig.in])	# File must be renamed
+AC_CONFIG_FILES([prealloc.h:prealloc.in])	# File must be renamed
 AC_CONFIG_FILES([cron/sysstat.cron.daily])
 AC_CONFIG_FILES([cron/sysstat.cron.hourly])
 AC_CONFIG_FILES([cron/sysstat.crond])

iconfig

@@ -88,6 +88,12 @@ if [ "${COMPRESSAFTER}" != "" ]; then
 	COMPRESSAFTER="compressafter=${COMPRESSAFTER} "
 fi
 
+# Preallocation factor
+PREALLOC_ANSWER=`${ASK} 'Preallocation factor value:' "prealloc" "prealloc"`
+if [ "${PREALLOC_ANSWER}" != "" ]; then
+	PREALLOC_ANSWER="prealloc=${PREALLOC_ANSWER} "
+fi
+
 # Manual page group
 MAN=`${ASK} 'Group for manual pages:' "man_group" "man_group"`
 if [ "${MAN}" != "" ]; then
@@ -194,11 +200,11 @@ fi
 
 echo
 echo "./configure ${PREFIX}${SA_LIB_DIR}${SA_DIR}${SYSCONFIG_DIR}${CLEAN_SA_DIR}${NLS} \
-${YESTERDAY}${HISTORY}${COMPRESSAFTER}${MAN}${IGNORE_MAN}${CRON}${RCDIR} \
+${YESTERDAY}${HISTORY}${COMPRESSAFTER}${PREALLOC_ANSWER}${MAN}${IGNORE_MAN}${CRON}${RCDIR} \
 ${COMPRESSMANPG}${INSTALL_DOC}${DEBUGINFO}${INSTALL_ISAG}${SENSORS}${STRIP}"
 echo
 
 ./configure ${PREFIX}${SA_LIB_DIR}${SA_DIR}${SYSCONFIG_DIR}${CLEAN_SA_DIR}${NLS} \
-${YESTERDAY}${HISTORY}${COMPRESSAFTER}${MAN}${IGNORE_MAN}${CRON}${RCDIR} \
+${YESTERDAY}${HISTORY}${COMPRESSAFTER}${PREALLOC_ANSWER}${MAN}${IGNORE_MAN}${CRON}${RCDIR} \
 ${COMPRESSMANPG}${INSTALL_DOC}${DEBUGINFO}${INSTALL_ISAG}${SENSORS}${STRIP}
 

prealloc.in

@@ -0,0 +1,17 @@
+/*
+ * sysstat: System performance tools for Linux
+ * (C) 1999-2013 by Sebastien Godard (sysstat <at> orange.fr)
+ */
+
+#ifndef _PREALLOC_H
+#define _PREALLOC_H
+
+/* Preallocation constants for sar */
+#define NR_IFACE_PREALLOC	(2 * @PREALLOC_FACTOR@)
+#define NR_SERIAL_PREALLOC	(2 * @PREALLOC_FACTOR@)
+#define NR_DISK_PREALLOC	(3 * @PREALLOC_FACTOR@)
+#define NR_FREQ_PREALLOC	(0 * @PREALLOC_FACTOR@)
+#define NR_USB_PREALLOC		(5 * @PREALLOC_FACTOR@)
+#define NR_FILESYSTEM_PREALLOC	(3 * @PREALLOC_FACTOR@)
+
+#endif  /* _PREALLOC_H */

sa.h

@@ -9,6 +9,7 @@
 #include <stdio.h>
 
 #include "common.h"
+#include "prealloc.h"
 #include "rd_stats.h"
 #include "rd_sensors.h"
 
@@ -192,14 +193,6 @@
  */
 #define BITMAP_SIZE(m)	((((m) + 1) / 8) + 1)
 
-/* Pre-allocation constants */
-#define NR_IFACE_PREALLOC	2
-#define NR_SERIAL_PREALLOC	2
-#define NR_DISK_PREALLOC	3
-#define NR_FREQ_PREALLOC	0
-#define NR_USB_PREALLOC		5
-#define NR_FILESYSTEM_PREALLOC	3
-
 #define UTSNAME_LEN		65
 #define TIMESTAMP_LEN		16
 #define HEADER_LINE_LEN		512