I have two Debian Linux servers with PPP connection over 4-
wired leased line.
Though the line is of very bad quolity I manage to do my job.
But when I tar a large archive files (about 3 GB) into tape PPP
connection begin to loss packets.
top reveals that tar utilises 10% - 20% of CPU. I hope the
amount of memmory is enough as both systems almost don't use
swap area.
Couldn't anyboby, please, tell me what can be the cause of the
problem, and what diagnostic utilities should I use in trying
to locate it.
Thank you, Mikhail.
PS I include configuration and logs into conf_logs.txt file
attached.
(tar is not running)
mikhailr@nagan:~$ ping liana
PING liana.angg.ru (172.31.0.1): 56 data bytes
64 bytes from 172.31.0.1: icmp_seq=0 ttl=255 time=183.5 ms
64 bytes from 172.31.0.1: icmp_seq=1 ttl=255 time=179.9 ms
64 bytes from 172.31.0.1: icmp_seq=2 ttl=255 time=170.0 ms
64 bytes from 172.31.0.1: icmp_seq=3 ttl=255 time=170.0 ms
64 bytes from 172.31.0.1: icmp_seq=4 ttl=255 time=179.9 ms
64 bytes from 172.31.0.1: icmp_seq=5 ttl=255 time=180.0 ms
64 bytes from 172.31.0.1: icmp_seq=6 ttl=255 time=170.0 ms
64 bytes from 172.31.0.1: icmp_seq=7 ttl=255 time=180.0 ms
64 bytes from 172.31.0.1: icmp_seq=8 ttl=255 time=160.0 ms
64 bytes from 172.31.0.1: icmp_seq=9 ttl=255 time=170.0 ms
64 bytes from 172.31.0.1: icmp_seq=10 ttl=255 time=170.0 ms
64 bytes from 172.31.0.1: icmp_seq=11 ttl=255 time=170.0 ms
64 bytes from 172.31.0.1: icmp_seq=12 ttl=255 time=170.0 ms
64 bytes from 172.31.0.1: icmp_seq=13 ttl=255 time=180.0 ms
64 bytes from 172.31.0.1: icmp_seq=14 ttl=255 time=180.0 ms
64 bytes from 172.31.0.1: icmp_seq=15 ttl=255 time=180.0 ms
--- liana.angg.ru ping statistics ---
16 packets transmitted, 16 packets received, 0% packet loss
round-trip min/avg/max = 160.0/174.5/183.5 ms
(tar is running)
mikhailr@nagan:~$ ping liana
PING liana.angg.ru (172.31.0.1): 56 data bytes
64 bytes from 172.31.0.1: icmp_seq=0 ttl=255 time=220.9 ms
64 bytes from 172.31.0.1: icmp_seq=1 ttl=255 time=183.7 ms
64 bytes from 172.31.0.1: icmp_seq=2 ttl=255 time=200.0 ms
64 bytes from 172.31.0.1: icmp_seq=3 ttl=255 time=190.0 ms (the next packet is lost)
64 bytes from 172.31.0.1: icmp_seq=5 ttl=255 time=180.0 ms
64 bytes from 172.31.0.1: icmp_seq=6 ttl=255 time=181.0 ms
64 bytes from 172.31.0.1: icmp_seq=7 ttl=255 time=190.0 ms
64 bytes from 172.31.0.1: icmp_seq=8 ttl=255 time=180.9 ms (the next packet is lost)
64 bytes from 172.31.0.1: icmp_seq=10 ttl=255 time=170.0 ms
64 bytes from 172.31.0.1: icmp_seq=11 ttl=255 time=170.0 ms
64 bytes from 172.31.0.1: icmp_seq=12 ttl=255 time=170.0 ms
--- liana.angg.ru ping statistics ---
15 packets transmitted, 11 packets received, 26% packet loss
round-trip min/avg/max = 170.0/185.1/220.9 ms
nagan:/etc# top
06:49:02 up 5:33, 2 users, load average: 1.12, 1.08, 1.33
56 processes: 54 sleeping, 2 running, 0 zombie, 0 stopped
CPU states: 0.2% user, 17.8% system, 0.0% nice, 82.0% idle
Mem: 772184K total, 767752K used, 4432K free, 24452K buffers
Swap: 265064K total, 2276K used, 262788K free, 610340K cached
PID USER PRI NI SIZE RSS SHARE STAT %CPU %MEM TIME COMMAND
2040 root 18 10 752 752 636 D N 11.3 0.0 8:56 tar
4 root 9 0 0 0 0 SW 1.7 0.0 2:13 kswapd
3 root 19 19 0 0 0 SWN 0.1 0.0 0:10 ksoftirqd_CPU0
3272 mikhailr 9 0 956 956 752 S 0.1 0.1 0:01 top
3284 root 10 0 952 952 752 R 0.1 0.1 0:00 top
[...]
Software used:
Debian Linux sid
kernel 2.4.18
libc6 2.2.15
ppp 2.4.1.uus
nagan:/etc# cat inittab
[...]
S0:23:respawn:/usr/sbin/pppd /dev/ttyS0 115200
S1:23:respawn:/usr/sbin/pppd /dev/ttyS1 115200
nagan:/etc/ppp# cat options.ttyS1
crtscts
mru 576
mtu 576
passive
10.0.0.2:
-chap
modem
noauth
-pap
persist
nodefaultroute
novj
novjccomp
nodetach
noproxyarp
asyncmap 0
lock
liana:/etc# cat inittab
[...]
T4:23:respawn:/usr/sbin/pppd /dev/ttyS0 115200 10.0.0.1:
liana:/etc/ppp# cat options.ttyS0
crtscts
mru 576
mtu 576
passive
-chap
modem
noauth
-pap
persist
nodetach
nodefaultroute
novj
novjccomp
asyncmap 0
lock
noproxyarp
mikhailr@nagan:~$ cat /var/log/dmesg
mikhailr@nagan:~$ cat /var/log/dmesg
Linux version 2.4.18 (root@nagan.angg.ru) (gcc version 2.95.4 20011002 (Debian prerelease)) #1 Sun Mar 17 11:02:39 YEKT 2002
BIOS-provided physical RAM map:
BIOS-e820: 0000000000000000 - 00000000000a0000 (usable)
BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 000000002fff0000 (usable)
BIOS-e820: 000000002fff0000 - 000000002fff3000 (ACPI NVS)
BIOS-e820: 000000002fff3000 - 0000000030000000 (ACPI data)
BIOS-e820: 00000000ffff0000 - 0000000100000000 (reserved)
On node 0 totalpages: 196592
zone(0): 4096 pages.
zone(1): 192496 pages.
zone(2): 0 pages.
Local APIC disabled by BIOS -- reenabling.
Found and enabled local APIC!
Kernel command line: auto BOOT_IMAGE=Linux ro root=301
Initializing CPU#0
Detected 851.955 MHz processor.
Console: colour VGA+ 80x25
Calibrating delay loop... 1697.38 BogoMIPS
Memory: 771952k/786368k available (969k kernel code, 14032k reserved, 297k data, 232k init, 0k highmem)
Dentry-cache hash table entries: 131072 (order: 8, 1048576 bytes)
Inode-cache hash table entries: 65536 (order: 7, 524288 bytes)
Mount-cache hash table entries: 16384 (order: 5, 131072 bytes)
Buffer-cache hash table entries: 65536 (order: 6, 262144 bytes)
Page-cache hash table entries: 262144 (order: 8, 1048576 bytes)
CPU: Before vendor init, caps: 0387fbff 00000000 00000000, vendor = 0
CPU: L1 I cache: 16K, L1 D cache: 16K
CPU: L2 cache: 256K
CPU: After vendor init, caps: 0387fbff 00000000 00000000 00000000
CPU serial number disabled.
Intel machine check architecture supported.
Intel machine check reporting enabled on CPU#0.
CPU: After generic, caps: 0383fbff 00000000 00000000 00000000
CPU: Common caps: 0383fbff 00000000 00000000 00000000
CPU: Intel Pentium III (Coppermine) stepping 06
Enabling fast FPU save and restore... done.
Enabling unmasked SIMD FPU exception support... done.
Checking 'hlt' instruction... OK.
POSIX conformance testing by UNIFIX
enabled ExtINT on CPU#0
ESR value before enabling vector: 00000000
ESR value after enabling vector: 00000000
Using local APIC timer interrupts.
calibrating APIC timer ...
..... CPU clock speed is 851.9498 MHz.
..... host bus clock speed is 100.2292 MHz.
cpu: 0, clocks: 1002292, slice: 501146
CPU0<T0:1002288,T1:501136,D:6,S:501146,C:1002292>
mtrr: v1.40 (20010327) Richard Gooch (rgooch@atnf.csiro.au)
mtrr: detected mtrr type: Intel
PCI: PCI BIOS revision 2.10 entry at 0xfb150, last bus=1
PCI: Using configuration type 1
PCI: Probing PCI hardware
Unknown bridge resource 0: assuming transparent
Unknown bridge resource 1: assuming transparent
Unknown bridge resource 2: assuming transparent
PCI: Using IRQ router VIA [1106/0596] at 00:02.0
Activating ISA DMA hang workarounds.
isapnp: Scanning for PnP cards...
isapnp: No Plug & Play device found
Linux NET4.0 for Linux 2.4
Based upon Swansea University Computer Society NET3.039
Initializing RT netlink socket
Starting kswapd
VFS: Diskquotas version dquot_6.4.0 initialized
Detected PS/2 Mouse Port.
pty: 256 Unix98 ptys configured
Serial driver version 5.05c (2001-07-08) with MANY_PORTS SHARE_IRQ SERIAL_PCI ISAPNP enabled
ttyS00 at 0x03f8 (irq = 4) is a 16550A
ttyS01 at 0x02f8 (irq = 3) is a 16550A
block: 128 slots per queue, batch=32
RAMDISK driver initialized: 16 RAM disks of 12288K size 1024 blocksize
Uniform Multi-Platform E-IDE driver Revision: 6.31
ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
VP_IDE: IDE controller on PCI bus 00 dev 11
VP_IDE: chipset revision 16
VP_IDE: not 100% native mode: will probe irqs later
ide0: BM-DMA at 0xe000-0xe007, BIOS settings: hda:DMA, hdb:DMA
ide1: BM-DMA at 0xe008-0xe00f, BIOS settings: hdc:pio, hdd:pio
hda: IBM-DTLA-307045, ATA DISK drive
hdb: IBM-DTLA-307020, ATA DISK drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
hda: 90069840 sectors (46116 MB) w/1916KiB Cache, CHS=5606/255/63
hdb: 40188960 sectors (20577 MB) w/1916KiB Cache, CHS=39870/16/63
Partition check:
hda: hda1 hda2 hda3 hda4 < hda5 hda6 hda7 hda8 hda9 hda10 hda11 >
hdb: hdb1 hdb2 hdb3 hdb4 < hdb5 hdb6 hdb7 hdb8 hdb9 hdb10 >
Floppy drive(s): fd0 is 1.44M
FDC 0 is a post-1991 82077
Linux agpgart interface v0.99 (c) Jeff Hartmann
agpgart: Maximum main memory to use for agp memory: 690M
agpgart: unsupported bridge
agpgart: no supported devices found.
SCSI subsystem driver Revision: 1.00
NET4: Linux TCP/IP 1.0 for NET4.0
IP Protocols: ICMP, UDP, TCP
IP: routing cache hash table of 8192 buckets, 64Kbytes
TCP: Hash tables configured (established 262144 bind 65536)
NET4: Unix domain sockets 1.0/SMP for Linux NET4.0.
VFS: Mounted root (ext2 filesystem) readonly.
Freeing unused kernel memory: 232k freed
Adding Swap: 265064k swap-space (priority -1)
Broadcom Gigabit Ethernet Driver bcm5700 with Broadcom NIC Extension (NICE) ver. 2.0.32 (01/02/02)
PCI: Found IRQ 10 for device 00:0e.0
eth0: 3Com 3C996 10/100/1000 Server NIC found at mem d5000000, IRQ 10, node addr 000476308391
eth0: Broadcom BCM5401 Copper transceiver found
eth0: Scatter-gather ON, 64-bit DMA ON, Tx Checksum ON, Rx Checksum ON
PCI: Found IRQ 11 for device 00:0f.0
PCI: Sharing IRQ 11 with 00:0b.0
scsi0 : Adaptec AIC7XXX EISA/VLB/PCI SCSI HBA DRIVER, Rev 6.2.4
<Adaptec 29160 Ultra160 SCSI adapter>
aic7892: Ultra160 Wide Channel A, SCSI Id=7, 32/253 SCBs
Vendor: HP Model: C1537A Rev: L812
Type: Sequential-Access ANSI SCSI revision: 02
(scsi0:A:3): 10.000MB/s transfers (10.000MHz, offset 32)
st: Version 20020205, bufsize 32768, wrt 30720, max init. bufs 4, s/g segs 16
Attached scsi tape st0 at scsi0, channel 0, id 3, lun 0
CSLIP: code copyright 1989 Regents of the University of California
PPP generic driver version 2.4.1
bcm5700: eth0 NIC Link is UP, 1000 Mbps full duplex
