[3023] in linux-net channel archive
PPP *outgoing* slow
daemon@ATHENA.MIT.EDU (athan@mersinet.co.uk)
Tue May 28 03:26:36 1996
To: linux-net@vger.rutgers.edu
Date: 28 May 1996 01:07:00 GMT
From: athan@mersinet.co.uk
Hi,
After experiencing all the troubles with PPP around 1.3.8x/1.3.9y
(x=8 or so, y=3 or so?), and thinking they were cleared up, I found it
wasn't entirely so.
I now get 'good' transfers INTO my machine (specs follow), but get
absolutely *AWFUL* transfer rates out of it.
Machine Specs:
486DX2-66, 8Mb RAM, Megahertz PCMCIA 14.4kpbs modem (setserial causing
its 16550A serial port to operate at 115.2kbps). Its a portable with VLB
graphics and a nice fast 340Mb Toshiba HD (128Kb cache *8-).
Kernel: 1.99.7 (plus noblink patch)
PPP: 2.2.0f
PCMCIA: 2.8.12
It runs a ppp link between itself and my other machine as well, which is
ppp0 (16450 UARTs either end set to 115.2kbps, drops a few packets here
and there). The external link is ppp1:
ppp1 Link encap:Point-Point Protocol
inet addr:194.222.25.24 P-t-P:158.152.1.222 Mask:255.255.255.0
UP POINTOPOINT RUNNING MTU:576 Metric:1
RX packets:19547 errors:0 dropped:0 overruns:0
TX packets:23376 errors:0 dropped:0 overruns:0
The phone line is nice and clean (BT engineer eventually put a filter on
it, before then we had LOTS of line noise problems, clear as a whistle
now).
orodruin:/usr/src/pcmcia-cs-2.8.12(bimble)> cat /proc/net/dev
Inter-| Receive | Transmit
face |packets errs drop fifo frame|packets errs drop fifo colls carrier
lo: 403 0 0 0 0 403 0 0 0 0 0
ppp0: 4889 23 23 0 0 3147 0 0 0 0 0
ppp1: 19977 0 0 0 0 23814 0 0 0 0 0
On INCOMING transfers I get a nice ~1.1KB/s transfer rate, about right
for the other traffic on the link.
On OUTGOING tranfers I get at most 50BYTES/s, sometimes as low as
12BYTES/s. tcpdump'ing of such connections shows burtss of activity
followed by great big pauses (it looks like it isn't re-sending packets
soon enough).
Throughout this interactive performance varies little.
This has been tested with the other end being a Linux box (9 hops
away, this machine is on demon, the other end is at mersinet.co.uk,
connected via BTNET) running either 1.2.13 or 1.3.94.
I thought initially it might have been to do with the firewalling I
have setup, maybe the filtering slowing things downin some pathological
way. To make sure I disabled it, and no difference was observed.
Kernel config is:
------------------------------------------------------------------------
#
# Automatically generated make config: don't edit
#
#
# Code maturity level options
#
CONFIG_EXPERIMENTAL=y
#
# Loadable module support
#
CONFIG_MODULES=y
CONFIG_MODVERSIONS=y
CONFIG_KERNELD=y
#
# General setup
#
# CONFIG_MATH_EMULATION is not set
CONFIG_NET=y
# CONFIG_MAX_16M is not set
# CONFIG_PCI is not set
CONFIG_SYSVIPC=y
CONFIG_BINFMT_AOUT=y
CONFIG_BINFMT_ELF=y
# CONFIG_BINFMT_JAVA is not set
CONFIG_KERNEL_ELF=y
# CONFIG_M386 is not set
CONFIG_M486=y
# CONFIG_M586 is not set
# CONFIG_M686 is not set
#
# Floppy, IDE, and other block devices
#
CONFIG_BLK_DEV_FD=m
CONFIG_BLK_DEV_IDE=y
#
# Please see drivers/block/README.ide for help/info on IDE drives
#
# CONFIG_BLK_DEV_HD_IDE is not set
# CONFIG_BLK_DEV_IDECD is not set
# CONFIG_BLK_DEV_IDETAPE is not set
# CONFIG_BLK_DEV_IDE_PCMCIA is not set
# CONFIG_BLK_DEV_CMD640 is not set
# CONFIG_IDE_CHIPSETS is not set
#
# Additional Block Devices
#
CONFIG_BLK_DEV_LOOP=m
# CONFIG_BLK_DEV_MD is not set
# CONFIG_BLK_DEV_RAM is not set
# CONFIG_BLK_DEV_XD is not set
#
# Networking options
#
CONFIG_FIREWALL=y
# CONFIG_NET_ALIAS is not set
CONFIG_INET=y
CONFIG_IP_FORWARD=y
# CONFIG_IP_MULTICAST is not set
CONFIG_IP_FIREWALL=y
CONFIG_IP_FIREWALL_VERBOSE=y
CONFIG_IP_MASQUERADE=y
# CONFIG_IP_TRANSPARENT_PROXY is not set
CONFIG_IP_ALWAYS_DEFRAG=y
CONFIG_IP_ACCT=y
# CONFIG_IP_ROUTER is not set
# CONFIG_NET_IPIP is not set
#
# (it is safe to leave these untouched)
#
CONFIG_INET_PCTCP=y
# CONFIG_INET_RARP is not set
# CONFIG_NO_PATH_MTU_DISCOVERY is not set
CONFIG_IP_NOSR=y
# CONFIG_SKB_LARGE is not set
#
#
#
# CONFIG_IPX is not set
# CONFIG_ATALK is not set
# CONFIG_AX25 is not set
# CONFIG_BRIDGE is not set
# CONFIG_NETLINK is not set
#
# SCSI support
#
# CONFIG_SCSI is not set
#
# Network device support
#
CONFIG_NETDEVICES=y
# CONFIG_DUMMY is not set
# CONFIG_EQUALIZER is not set
# CONFIG_DLCI is not set
# CONFIG_PLIP is not set
CONFIG_PPP=m
#
# CCP compressors for PPP are only built as modules.
#
CONFIG_SLIP=m
CONFIG_SLIP_COMPRESSED=y
CONFIG_SLIP_SMART=y
# CONFIG_SLIP_MODE_SLIP6 is not set
# CONFIG_NET_RADIO is not set
# CONFIG_NET_ETHERNET is not set
# CONFIG_TR is not set
# CONFIG_ARCNET is not set
#
# ISDN subsystem
#
# CONFIG_ISDN is not set
#
# CD-ROM drivers (not for SCSI or IDE/ATAPI drives)
#
# CONFIG_CD_NO_IDESCSI is not set
#
# Filesystems
#
CONFIG_QUOTA=y
# CONFIG_LOCK_MANDATORY is not set
CONFIG_MINIX_FS=y
# CONFIG_EXT_FS is not set
CONFIG_EXT2_FS=y
# CONFIG_XIA_FS is not set
CONFIG_FAT_FS=m
CONFIG_MSDOS_FS=m
# CONFIG_VFAT_FS is not set
# CONFIG_UMSDOS_FS is not set
CONFIG_PROC_FS=y
CONFIG_NFS_FS=m
# CONFIG_SMB_FS is not set
# CONFIG_ISO9660_FS is not set
# CONFIG_HPFS_FS is not set
# CONFIG_SYSV_FS is not set
# CONFIG_AFFS_FS is not set
# CONFIG_UFS_FS is not set
#
# Character devices
#
CONFIG_SERIAL=y
# CONFIG_DIGI is not set
# CONFIG_CYCLADES is not set
# CONFIG_STALDRV is not set
# CONFIG_RISCOM8 is not set
CONFIG_PRINTER=m
# CONFIG_BUSMOUSE is not set
# CONFIG_PSMOUSE is not set
# CONFIG_MS_BUSMOUSE is not set
# CONFIG_ATIXL_BUSMOUSE is not set
# CONFIG_UMISC is not set
# CONFIG_QIC02_TAPE is not set
# CONFIG_FTAPE is not set
# CONFIG_APM is not set
CONFIG_WATCHDOG=y
# CONFIG_WATCHDOG_NOWAYOUT is not set
# CONFIG_WDT is not set
CONFIG_SOFT_WATCHDOG=m
# CONFIG_RTC is not set
#
# Sound
#
# CONFIG_SOUND is not set
#
# Kernel hacking
#
# CONFIG_PROFILE is not set
------------------------------------------------------------------------
If I've missed any useful information off, or can carry out any tests,
including kernel patches *PLEASE* let me know. I read this list, but
give then vger delays direct email as well may be a good idea. If you
don't mind calling a UK mobile phone I can talk to you as well whilst
testing (only one 'normal' phone line...).
If requested I'll rerun the tests and save the tcpdump output for
perusal by one and all (I can make it available via anon ftp).
hoping to get this pinned down...
-Neil
--
**************************************************************************
* Neil Soveran-Charley, System Administrator, Mersinet Internet Services *
* Email: N.P.Soveran-Charley@mersinet.co.uk *
**************************************************************************
