[Bug 782092] Re: ssh server extremly unresponsive

[Martin Konopka]

apport information

** Tags added: apport-collected

** Description changed:

  I describe the issue in few steps below.
  
  1.) I want to transfer files from machine A (with ubuntu 11.04, but this
  is not important) to machine B (ubuntu 10.10; this is important to say)
  using scp.
  
  2.) Machine B is under constant computational load due to a user program
  (a simulation) such that most of its CPU power is consumed by the
  program but it uses less then half of total (12 GB) memory and there is
  not any significant usage of disk and no other application is running.
  (Even no user logged into a GNOME session.)
  
  3.) I issue the command scp on machine A; I immediatelly get prompt to
  give password. However the transfer does not start immediatelly after
  that. I must wait for some time, say half a minute or even full minute
  or more (I have not measured it.) just to see the start of the tranfer.
  
  Few additional remarks:
  
  Until recently machine B had had installed ubuntu 10.04 (Lucid Lynx,
  64-bit) and there was no such problem even at higher computational
  loads. Similarly there was no such problem even in more distant past
  when the machine was running under Linux Mint Helena (based upon Ubuntu
  9.10).
  
  The long delays when doing scp occur if machine B was not exposed to an
  scp or ssh demand for a longer period of time. (Typically I face the
  problem in the morning when.) If an scp transfer is finally accomplished
  then I can start a new one which already works without delay.
  
  Machine B is equipped with an Intel i7 CPU, 12 GB of DDR3 and it is a
  quite powerful workstation. All cores of CPU are set to run at maximum
  frequency.
  
  I attach a file with content shown by the program top. (Grabbed in
  situation when a user is logged into GNOME session.)
  
  ProblemType: Bug
  DistroRelease: Ubuntu 10.10
  Package: openssh-server 1:5.5p1-4ubuntu5
  ProcVersionSignature: Ubuntu 2.6.35-28.50-generic 2.6.35.11
  Uname: Linux 2.6.35-28-generic x86_64
  Architecture: amd64
  Date: Fri May 13 10:39:53 2011
  InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release amd64 (20101007)
  ProcEnviron:
   LANGUAGE=en_GB:en
   PATH=(custom, user)
   LANG=en_GB.utf8
   SHELL=/bin/bash
  SourcePackage: openssh
+ --- 
+ AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.23.
+ Architecture: amd64
+ AudioDevicesInUse:
+  USER        PID ACCESS COMMAND
+  /dev/snd/controlC0:  konopka   12733 F.... pulseaudio
+ CRDA: Error: [Errno 2] No such file or directory
+ Card0.Amixer.info:
+  Card hw:0 'Intel'/'HDA Intel at 0xd7ff8000 irq 73'
+    Mixer name	: 'Analog Devices AD1989B'
+    Components	: 'HDA:11d4989b,10438372,00100300'
+    Controls      : 48
+    Simple ctrls  : 27
+ DistroRelease: Ubuntu 10.10
+ HibernationDevice: RESUME=UUID=c49e29ce-51d0-4841-ba53-2277847b7096
+ InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release amd64 (20101007)
+ IwConfig:
+  lo        no wireless extensions.
+  
+  eth0      no wireless extensions.
+  
+  eth1      no wireless extensions.
+ MachineType: System manufacturer System Product Name
+ Package: openssh
+ ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-2.6.35-30-generic root=UUID=ed65d6b9-ca7c-4627-808f-b9f882327a13 ro quiet splash
+ ProcEnviron:
+  LANGUAGE=en_GB:en
+  PATH=(custom, user)
+  LANG=en_GB.utf8
+  SHELL=/bin/bash
+ ProcVersionSignature: Ubuntu 2.6.35-30.54-generic 2.6.35.13
+ Regression: Yes
+ RelatedPackageVersions: linux-firmware 1.38.6
+ Reproducible: Yes
+ RfKill:
+  
+ Tags: maverick kernel-config regression-release needs-upstream-testing
+ Uname: Linux 2.6.35-30-generic x86_64
+ UserGroups: adm admin cdrom dialout lpadmin plugdev sambashare
+ WifiSyslog:
+  
+ dmi.bios.date: 11/12/2009
+ dmi.bios.vendor: American Megatrends Inc.
+ dmi.bios.version: 0704
+ dmi.board.asset.tag: To Be Filled By O.E.M.
+ dmi.board.name: P6T DELUXE V2
+ dmi.board.vendor: ASUSTeK Computer INC.
+ dmi.board.version: Rev 1.xx
+ dmi.chassis.asset.tag: Asset-1234567890
+ dmi.chassis.type: 3
+ dmi.chassis.vendor: Chassis Manufacture
+ dmi.chassis.version: Chassis Version
+ dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr0704:bd11/12/2009:svnSystemmanufacturer:pnSystemProductName:pvrSystemVersion:rvnASUSTeKComputerINC.:rnP6TDELUXEV2:rvrRev1.xx:cvnChassisManufacture:ct3:cvrChassisVersion:
+ dmi.product.name: System Product Name
+ dmi.product.version: System Version
+ dmi.sys.vendor: System manufacturer

** Attachment added: "AcpiTables.txt"
   https://bugs.edge.launchpad.net/bugs/782092/+attachment/2216695/+files/AcpiTables.txt

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Title:
  ssh server extremly unresponsive

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