possible leak in kernel 2.6.10-ac12

[Pedro Venda <pjvenda@arrakis.dhis.org>]

hi everyone,

I maintain a couple of linux servers in an academic environment.
Having upgraded most of them to 2.6.10-ac12, one of them showed a linear
growth of used memory over the last 7 days, after the first 2.6.10-ac12
boot. It came to a point that it started swapping and the swap usage too
started to grow linearly.

Most of the userspace memory was occupied by postfix and spamassassin
processes, which after killed didn't stop the memory growth, so I'm left
with the feeling of a kernel memory leak.

This is mostly an e-mail server:
* smtp for about 300 hosts (postfix)
* 6 local e-mail accounts for in-house administrators
** spamassassin for the local accounts
** courier-imap-ssl for the local accounts
Running on a 2.0GHz P4 with 512Mb of ram.
kernel version is 2.6.10-ac12 [1]
kernel config: [2]

Since this is a production machine, I can't test it very thouroughly
(lots of reboots, etc), but I'd like to know more about this.

I had to reboot it, so it's all normal now.

If the behavior maintains, how can I infer if there is really a memory
leak? What kind of tests could I perform?

best regards,
pedro venda.

----------------------------------------------------------------------

[1]: ver_linux output
Linux admin 2.6.10-ac12 #1 Wed Feb 9 01:53:22 WET 2005 i686 Intel(R)
Pentium(R)
4 CPU 2.00GHz GenuineIntel GNU/Linux

Gnu C                  3.3.5
Gnu make               3.80
binutils               2.15.92.0.2
util-linux             2.12i
mount                  2.12i
module-init-tools      3.0
e2fsprogs              1.35
reiserfsprogs          3.6.19
reiser4progs           line
Linux C Library        2.3.4
Dynamic linker (ldd)   2.3.4
Procps                 3.2.4
Net-tools              1.60
Kbd                    1.12
Sh-utils               5.2.1
Modules Loaded         ipt_state ip_conntrack iptable_filter ip_tables
eepro100
i2c_i801 i2c_core 8139too crc32

[2]: kernel config
CONFIG_X86=y
CONFIG_MMU=y
CONFIG_UID16=y
CONFIG_GENERIC_ISA_DMA=y
CONFIG_GENERIC_IOMAP=y
CONFIG_EXPERIMENTAL=y
CONFIG_CLEAN_COMPILE=y
CONFIG_BROKEN_ON_SMP=y
CONFIG_LOCALVERSION=""
CONFIG_SWAP=y
CONFIG_SYSVIPC=y
CONFIG_POSIX_MQUEUE=y
CONFIG_BSD_PROCESS_ACCT=y
CONFIG_BSD_PROCESS_ACCT_V3=y
CONFIG_SYSCTL=y
CONFIG_AUDIT=y
CONFIG_AUDITSYSCALL=y
CONFIG_LOG_BUF_SHIFT=14
CONFIG_KOBJECT_UEVENT=y
CONFIG_IKCONFIG=y
CONFIG_IKCONFIG_PROC=y
CONFIG_KALLSYMS=y
CONFIG_FUTEX=y
CONFIG_EPOLL=y
CONFIG_SHMEM=y
CONFIG_CC_ALIGN_FUNCTIONS=0
CONFIG_CC_ALIGN_LABELS=0
CONFIG_CC_ALIGN_LOOPS=0
CONFIG_CC_ALIGN_JUMPS=0
CONFIG_MODULES=y
CONFIG_MODULE_UNLOAD=y
CONFIG_MODULE_FORCE_UNLOAD=y
CONFIG_OBSOLETE_MODPARM=y
CONFIG_KMOD=y
CONFIG_X86_PC=y
CONFIG_MPENTIUM4=y
CONFIG_X86_HZ=1000
CONFIG_X86_GENERIC=y
CONFIG_X86_CMPXCHG=y
CONFIG_X86_XADD=y
CONFIG_X86_L1_CACHE_SHIFT=7
CONFIG_RWSEM_XCHGADD_ALGORITHM=y
CONFIG_X86_WP_WORKS_OK=y
CONFIG_X86_INVLPG=y
CONFIG_X86_BSWAP=y
CONFIG_X86_POPAD_OK=y
CONFIG_X86_GOOD_APIC=y
CONFIG_X86_INTEL_USERCOPY=y
CONFIG_X86_USE_PPRO_CHECKSUM=y
CONFIG_HPET_TIMER=y
CONFIG_X86_TSC=y
CONFIG_X86_MCE=y
CONFIG_X86_MCE_NONFATAL=m
CONFIG_MICROCODE=m
CONFIG_X86_MSR=m
CONFIG_X86_CPUID=m
CONFIG_NOHIGHMEM=y
CONFIG_MTRR=y
CONFIG_PM=y
CONFIG_ACPI=y
CONFIG_ACPI_BOOT=y
CONFIG_ACPI_INTERPRETER=y
CONFIG_ACPI_AC=m
CONFIG_ACPI_BATTERY=m
CONFIG_ACPI_BUTTON=m
CONFIG_ACPI_VIDEO=m
CONFIG_ACPI_FAN=m
CONFIG_ACPI_PROCESSOR=m
CONFIG_ACPI_THERMAL=m
CONFIG_ACPI_IBM=m
CONFIG_ACPI_BLACKLIST_YEAR=0
CONFIG_ACPI_BUS=y
CONFIG_ACPI_EC=y
CONFIG_ACPI_POWER=y
CONFIG_ACPI_PCI=y
CONFIG_ACPI_SYSTEM=y
CONFIG_APM=m
CONFIG_APM_DO_ENABLE=y
CONFIG_APM_CPU_IDLE=y
CONFIG_APM_DISPLAY_BLANK=y
CONFIG_CPU_FREQ=y
CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y
CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
CONFIG_CPU_FREQ_GOV_POWERSAVE=m
CONFIG_CPU_FREQ_GOV_USERSPACE=m
CONFIG_CPU_FREQ_TABLE=y
CONFIG_X86_ACPI_CPUFREQ=m
CONFIG_X86_P4_CLOCKMOD=m
CONFIG_X86_SPEEDSTEP_LIB=m
CONFIG_PCI=y
CONFIG_PCI_GOANY=y
CONFIG_PCI_BIOS=y
CONFIG_PCI_DIRECT=y
CONFIG_PCI_MMCONFIG=y
CONFIG_PCI_LEGACY_PROC=y
CONFIG_PCI_NAMES=y
CONFIG_ISA=y
CONFIG_BINFMT_ELF=y
CONFIG_BINFMT_AOUT=m
CONFIG_BINFMT_MISC=m
CONFIG_STANDALONE=y
CONFIG_PREVENT_FIRMWARE_BUILD=y
CONFIG_PARPORT=y
CONFIG_PARPORT_PC=y
CONFIG_PARPORT_PC_CML1=y
CONFIG_PARPORT_PC_FIFO=y
CONFIG_PARPORT_PC_SUPERIO=y
CONFIG_PARPORT_OTHER=y
CONFIG_PARPORT_1284=y
CONFIG_PNP=y
CONFIG_ISAPNP=y
CONFIG_PNPBIOS=y
CONFIG_PNPBIOS_PROC_FS=y
CONFIG_PNPACPI=y
CONFIG_BLK_DEV_FD=y
CONFIG_BLK_DEV_LOOP=m
CONFIG_BLK_DEV_CRYPTOLOOP=m
CONFIG_BLK_DEV_RAM_COUNT=16
CONFIG_INITRAMFS_SOURCE=""
CONFIG_IOSCHED_NOOP=y
CONFIG_IOSCHED_AS=y
CONFIG_IOSCHED_DEADLINE=y
CONFIG_IOSCHED_CFQ=y
CONFIG_IDE=y
CONFIG_BLK_DEV_IDE=y
CONFIG_BLK_DEV_IDEDISK=y
CONFIG_BLK_DEV_IDECD=y
CONFIG_IDE_TASK_IOCTL=y
CONFIG_IDE_GENERIC=y
CONFIG_BLK_DEV_IDEPCI=y
CONFIG_IDEPCI_SHARE_IRQ=y
CONFIG_BLK_DEV_GENERIC=y
CONFIG_BLK_DEV_IDEDMA_PCI=y
CONFIG_IDEDMA_PCI_AUTO=y
CONFIG_BLK_DEV_PIIX=y
CONFIG_BLK_DEV_IDEDMA=y
CONFIG_IDEDMA_AUTO=y
CONFIG_SCSI=y
CONFIG_SCSI_QLA2XXX=y
CONFIG_MD=y
CONFIG_BLK_DEV_MD=y
CONFIG_MD_RAID1=y
CONFIG_IEEE1394=m
CONFIG_IEEE1394_EXTRA_CONFIG_ROMS=y
CONFIG_IEEE1394_CONFIG_ROM_IP1394=y
CONFIG_IEEE1394_OHCI1394=m
CONFIG_IEEE1394_VIDEO1394=m
CONFIG_IEEE1394_SBP2=m
CONFIG_IEEE1394_ETH1394=m
CONFIG_IEEE1394_DV1394=m
CONFIG_IEEE1394_RAWIO=m
CONFIG_IEEE1394_CMP=m
CONFIG_NET=y
CONFIG_PACKET=y
CONFIG_PACKET_MMAP=y
CONFIG_UNIX=y
CONFIG_NET_KEY=y
CONFIG_INET=y
CONFIG_IP_MULTICAST=y
CONFIG_INET_AH=m
CONFIG_INET_ESP=m
CONFIG_INET_IPCOMP=m
CONFIG_INET_TUNNEL=m
CONFIG_IP_TCPDIAG=y
CONFIG_IP_TCPDIAG_IPV6=y
CONFIG_IPV6=y
CONFIG_IPV6_PRIVACY=y
CONFIG_INET6_AH=y
CONFIG_INET6_ESP=y
CONFIG_INET6_IPCOMP=y
CONFIG_INET6_TUNNEL=y
CONFIG_IPV6_TUNNEL=y
CONFIG_NETFILTER=y
CONFIG_IP_NF_CONNTRACK=m
CONFIG_IP_NF_FTP=m
CONFIG_IP_NF_IRC=m
CONFIG_IP_NF_TFTP=m
CONFIG_IP_NF_AMANDA=m
CONFIG_IP_NF_QUEUE=m
CONFIG_IP_NF_IPTABLES=m
CONFIG_IP_NF_MATCH_LIMIT=m
CONFIG_IP_NF_MATCH_IPRANGE=m
CONFIG_IP_NF_MATCH_MAC=m
CONFIG_IP_NF_MATCH_PKTTYPE=m
CONFIG_IP_NF_MATCH_MARK=m
CONFIG_IP_NF_MATCH_MULTIPORT=m
CONFIG_IP_NF_MATCH_TOS=m
CONFIG_IP_NF_MATCH_RECENT=m
CONFIG_IP_NF_MATCH_ECN=m
CONFIG_IP_NF_MATCH_DSCP=m
CONFIG_IP_NF_MATCH_AH_ESP=m
CONFIG_IP_NF_MATCH_LENGTH=m
CONFIG_IP_NF_MATCH_TTL=m
CONFIG_IP_NF_MATCH_TCPMSS=m
CONFIG_IP_NF_MATCH_HELPER=m
CONFIG_IP_NF_MATCH_STATE=m
CONFIG_IP_NF_MATCH_CONNTRACK=m
CONFIG_IP_NF_MATCH_OWNER=m
CONFIG_IP_NF_MATCH_ADDRTYPE=m
CONFIG_IP_NF_MATCH_REALM=m
CONFIG_IP_NF_FILTER=m
CONFIG_IP_NF_TARGET_REJECT=m
CONFIG_IP_NF_TARGET_LOG=m
CONFIG_IP_NF_TARGET_ULOG=m
CONFIG_IP_NF_TARGET_TCPMSS=m
CONFIG_IP_NF_NAT=m
CONFIG_IP_NF_NAT_NEEDED=y
CONFIG_IP_NF_TARGET_MASQUERADE=m
CONFIG_IP_NF_TARGET_REDIRECT=m
CONFIG_IP_NF_TARGET_NETMAP=m
CONFIG_IP_NF_TARGET_SAME=m
CONFIG_IP_NF_NAT_LOCAL=y
CONFIG_IP_NF_NAT_SNMP_BASIC=m
CONFIG_IP_NF_NAT_IRC=m
CONFIG_IP_NF_NAT_FTP=m
CONFIG_IP_NF_NAT_TFTP=m
CONFIG_IP_NF_NAT_AMANDA=m
CONFIG_IP_NF_MANGLE=m
CONFIG_IP_NF_TARGET_TOS=m
CONFIG_IP_NF_TARGET_ECN=m
CONFIG_IP_NF_TARGET_DSCP=m
CONFIG_IP_NF_TARGET_MARK=m
CONFIG_IP_NF_TARGET_CLASSIFY=m
CONFIG_IP_NF_RAW=m
CONFIG_IP_NF_TARGET_NOTRACK=m
CONFIG_IP_NF_ARPTABLES=y
CONFIG_IP_NF_ARPFILTER=y
CONFIG_IP_NF_ARP_MANGLE=y
CONFIG_IP6_NF_QUEUE=m
CONFIG_IP6_NF_IPTABLES=m
CONFIG_IP6_NF_MATCH_LIMIT=m
CONFIG_IP6_NF_MATCH_MAC=m
CONFIG_IP6_NF_MATCH_RT=m
CONFIG_IP6_NF_MATCH_OPTS=m
CONFIG_IP6_NF_MATCH_FRAG=m
CONFIG_IP6_NF_MATCH_HL=m
CONFIG_IP6_NF_MATCH_MULTIPORT=m
CONFIG_IP6_NF_MATCH_OWNER=m
CONFIG_IP6_NF_MATCH_MARK=m
CONFIG_IP6_NF_MATCH_IPV6HEADER=m
CONFIG_IP6_NF_MATCH_AHESP=m
CONFIG_IP6_NF_MATCH_LENGTH=m
CONFIG_IP6_NF_MATCH_EUI64=m
CONFIG_IP6_NF_FILTER=m
CONFIG_IP6_NF_TARGET_LOG=m
CONFIG_IP6_NF_MANGLE=m
CONFIG_IP6_NF_TARGET_MARK=m
CONFIG_IP6_NF_RAW=m
CONFIG_XFRM=y
CONFIG_NET_CLS_ROUTE=y
CONFIG_NETDEVICES=y
CONFIG_DUMMY=m
CONFIG_NET_ETHERNET=y
CONFIG_MII=y
CONFIG_NET_VENDOR_3COM=y
CONFIG_EL3=m
CONFIG_VORTEX=m
CONFIG_NET_TULIP=y
CONFIG_DE2104X=m
CONFIG_TULIP=m
CONFIG_DE4X5=m
CONFIG_WINBOND_840=m
CONFIG_DM9102=m
CONFIG_NET_PCI=y
CONFIG_EEPRO100=m
CONFIG_8139CP=m
CONFIG_8139TOO=m
CONFIG_8139TOO_PIO=y
CONFIG_8139TOO_TUNE_TWISTER=y
CONFIG_8139TOO_8129=y
CONFIG_INPUT=y
CONFIG_INPUT_MOUSEDEV=y
CONFIG_INPUT_MOUSEDEV_PSAUX=y
CONFIG_INPUT_MOUSEDEV_SCREEN_X=1024
CONFIG_INPUT_MOUSEDEV_SCREEN_Y=768
CONFIG_SOUND_GAMEPORT=y
CONFIG_SERIO=y
CONFIG_SERIO_I8042=y
CONFIG_INPUT_KEYBOARD=y
CONFIG_KEYBOARD_ATKBD=y
CONFIG_INPUT_MOUSE=y
CONFIG_MOUSE_PS2=y
CONFIG_VT=y
CONFIG_VT_CONSOLE=y
CONFIG_HW_CONSOLE=y
CONFIG_SERIAL_8250=y
CONFIG_SERIAL_8250_CONSOLE=y
CONFIG_SERIAL_8250_ACPI=y
CONFIG_SERIAL_8250_NR_UARTS=4
CONFIG_SERIAL_CORE=y
CONFIG_SERIAL_CORE_CONSOLE=y
CONFIG_UNIX98_PTYS=y
CONFIG_LEGACY_PTYS=y
CONFIG_LEGACY_PTY_COUNT=256
CONFIG_PRINTER=y
CONFIG_HW_RANDOM=y
CONFIG_NVRAM=y
CONFIG_RTC=y
CONFIG_HPET=y
CONFIG_HPET_RTC_IRQ=y
CONFIG_HPET_MMAP=y
CONFIG_HANGCHECK_TIMER=y
CONFIG_I2C=m
CONFIG_I2C_CHARDEV=m
CONFIG_I2C_ALGOBIT=m
CONFIG_I2C_ALGOPCF=m
CONFIG_I2C_ALI1535=m
CONFIG_I2C_ALI1563=m
CONFIG_I2C_ALI15X3=m
CONFIG_I2C_AMD756=m
CONFIG_I2C_AMD8111=m
CONFIG_I2C_ELEKTOR=m
CONFIG_I2C_I801=m
CONFIG_I2C_I810=m
CONFIG_I2C_ISA=m
CONFIG_I2C_NFORCE2=m
CONFIG_I2C_PARPORT=m
CONFIG_I2C_PARPORT_LIGHT=m
CONFIG_I2C_PIIX4=m
CONFIG_I2C_PROSAVAGE=m
CONFIG_I2C_SAVAGE4=m
CONFIG_SCx200_ACB=m
CONFIG_I2C_SIS5595=m
CONFIG_I2C_SIS630=m
CONFIG_I2C_SIS96X=m
CONFIG_I2C_VIA=m
CONFIG_I2C_VIAPRO=m
CONFIG_I2C_VOODOO3=m
CONFIG_I2C_SENSOR=m
CONFIG_SENSORS_ADM1021=m
CONFIG_SENSORS_ADM1025=m
CONFIG_SENSORS_ADM1031=m
CONFIG_SENSORS_ASB100=m
CONFIG_SENSORS_DS1621=m
CONFIG_SENSORS_FSCHER=m
CONFIG_SENSORS_GL518SM=m
CONFIG_SENSORS_IT87=m
CONFIG_SENSORS_LM75=m
CONFIG_SENSORS_LM77=m
CONFIG_SENSORS_LM78=m
CONFIG_SENSORS_LM80=m
CONFIG_SENSORS_LM83=m
CONFIG_SENSORS_LM85=m
CONFIG_SENSORS_LM90=m
CONFIG_SENSORS_MAX1619=m
CONFIG_SENSORS_VIA686A=m
CONFIG_SENSORS_W83781D=m
CONFIG_SENSORS_W83L785TS=m
CONFIG_SENSORS_W83627HF=m
CONFIG_FB=y
CONFIG_FB_VESA=y
CONFIG_VGA_CONSOLE=y
CONFIG_DUMMY_CONSOLE=y
CONFIG_LOGO=y
CONFIG_LOGO_LINUX_MONO=y
CONFIG_LOGO_LINUX_VGA16=y
CONFIG_LOGO_LINUX_CLUT224=y
CONFIG_USB_ARCH_HAS_HCD=y
CONFIG_USB_ARCH_HAS_OHCI=y
CONFIG_EXT2_FS=y
CONFIG_EXT2_FS_XATTR=y
CONFIG_EXT2_FS_POSIX_ACL=y
CONFIG_EXT2_FS_SECURITY=y
CONFIG_EXT3_FS=y
CONFIG_EXT3_FS_XATTR=y
CONFIG_EXT3_FS_POSIX_ACL=y
CONFIG_EXT3_FS_SECURITY=y
CONFIG_JBD=y
CONFIG_FS_MBCACHE=y
CONFIG_REISERFS_FS=y
CONFIG_REISERFS_PROC_INFO=y
CONFIG_REISERFS_FS_XATTR=y
CONFIG_REISERFS_FS_POSIX_ACL=y
CONFIG_REISERFS_FS_SECURITY=y
CONFIG_FS_POSIX_ACL=y
CONFIG_QUOTA=y
CONFIG_QFMT_V1=m
CONFIG_QFMT_V2=m
CONFIG_QUOTACTL=y
CONFIG_DNOTIFY=y
CONFIG_AUTOFS4_FS=y
CONFIG_ISO9660_FS=y
CONFIG_JOLIET=y
CONFIG_ZISOFS=y
CONFIG_ZISOFS_FS=y
CONFIG_UDF_FS=y
CONFIG_UDF_NLS=y
CONFIG_FAT_FS=y
CONFIG_MSDOS_FS=y
CONFIG_VFAT_FS=y
CONFIG_FAT_DEFAULT_CODEPAGE=860
CONFIG_FAT_DEFAULT_IOCHARSET="iso8859-15"
CONFIG_NTFS_FS=y
CONFIG_PROC_FS=y
CONFIG_PROC_KCORE=y
CONFIG_SYSFS=y
CONFIG_DEVFS_FS=y
CONFIG_DEVFS_MOUNT=y
CONFIG_DEVPTS_FS_XATTR=y
CONFIG_DEVPTS_FS_SECURITY=y
CONFIG_TMPFS=y
CONFIG_RAMFS=y
CONFIG_SMB_FS=m
CONFIG_MSDOS_PARTITION=y
CONFIG_NLS=y
CONFIG_NLS_DEFAULT="iso8859-15"
CONFIG_NLS_CODEPAGE_437=y
CONFIG_NLS_CODEPAGE_850=y
CONFIG_NLS_CODEPAGE_860=y
CONFIG_NLS_ISO8859_1=y
CONFIG_NLS_ISO8859_15=y
CONFIG_EARLY_PRINTK=y
CONFIG_4KSTACKS=y
CONFIG_CRYPTO=y
CONFIG_CRYPTO_HMAC=y
CONFIG_CRYPTO_NULL=m
CONFIG_CRYPTO_MD4=m
CONFIG_CRYPTO_MD5=y
CONFIG_CRYPTO_SHA1=y
CONFIG_CRYPTO_SHA256=m
CONFIG_CRYPTO_SHA512=m
CONFIG_CRYPTO_DES=y
CONFIG_CRYPTO_BLOWFISH=m
CONFIG_CRYPTO_TWOFISH=m
CONFIG_CRYPTO_SERPENT=m
CONFIG_CRYPTO_AES_586=m
CONFIG_CRYPTO_CAST5=m
CONFIG_CRYPTO_CAST6=m
CONFIG_CRYPTO_TEA=m
CONFIG_CRYPTO_ARC4=m
CONFIG_CRYPTO_KHAZAD=m
CONFIG_CRYPTO_DEFLATE=y
CONFIG_CRYPTO_MICHAEL_MIC=m
CONFIG_CRYPTO_CRC32C=m
CONFIG_CRYPTO_TEST=m
CONFIG_CRC_CCITT=m
CONFIG_CRC32=m
CONFIG_LIBCRC32C=m
CONFIG_ZLIB_INFLATE=y
CONFIG_ZLIB_DEFLATE=y
CONFIG_GENERIC_HARDIRQS=y
CONFIG_GENERIC_IRQ_PROBE=y
CONFIG_X86_BIOS_REBOOT=y
CONFIG_PC=y

-- 

Pedro João Lopes Venda
email: pjvenda < at > arrakis.dhis.org
http://arrakis.dhis.org