Code Development on NT Some notes on experience gained in developing crossplatform NTUnix HEP softwa

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Code Development on NTSome notes on experience
gained in developing cross-platform (NT/Unix) HEP
software for the Linear Collider DetectorMore
of a Random Walk than a Formal Overview of
Development Tools

• HEP-NT workshop
• SLAC - October 1999
• Tony Johnson
• Tony Waite
• (tonyj,apw_at_slac.stanford.edu)

In absentia
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NT Code Development

• Topics
• NT Code development tools for C/Fortran/Java
• Code development issues
• Code management
• SourceSafe
• CVS
• DEC -
• Using NT as a data server
• Conclusions

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Windows NT Development Tools

• For windows only development, tools are
  excellent
• Visual C/J (MS Java)/Compaq Fortran
• Excellent IDE allows development in all three
  languages
• Integrated editor, cross-language debugger
• Integrated build tool (make clone)
• Incremental linker (that works)
• Integrated code management (visual sourcesafe)
• Object browser
• SLAC has site license for MS developer tools

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C for cross platform development

• Cross Platform C development has many problems
• Makefile for each platform
• Need to build/debug on each platform
• Versionitis
• External dependencies
• Compiler flags
• Even egcs compiler has many system specific flags
• Different methods for building DLLs/C name
  mangling
• Compiler bugs
• Differing Levels of ANSI/STL Support
• Architecture specific bugs
• Found bugs in both Visual C (5.0) and egcs
  compiler for intel.

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C for cross-platform development

• Certainly possible - Simulation package does work
  on both NT and Unix.

Large amount of time goes into testing/debugging
on different platforms.
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Java for Cross Platform Development

• Have succeeded in writing entire
  reconstruction/analysis package in Java
• Currently using Visual J/Sourcesafe
• All development currently being done on NT
• JAR files built on NT and put on web server for
  download by others.
• Java code can be run
• Standalone from command prompt/batch job
• Inside Java Analysis Studio (JAS)

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Java Analysis Studio

• Cross Platform Java GUI for data analysis

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Java for cross-platform Graphics/GUI
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Java Experience

• Write Once Run Anywhere
• Really works (for applications, if not applets).
• Develop on NT, runs without changes elsewhere
• Developers have been able to learn language and
  tools and get up-to-speed fast
• Performance - Adequate, getting better all the
  time
• Need to abandon Visual J, Source Safe

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CVS for cross platform development

• CVS is available for NT as well as Unix
• NT tools include
• line mode tools
• WinCVS
• Rather confusing GUI
• jCVS
• Cross platform CVS GUI written in Java
• Doesnt support ssh access to remote repository?
• Several tools available for web based access to
  code
• CVSWeb - perl script
• jCVS servlet - works well on NT

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jCVS Client
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jCVS Servlet
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CVS security issues

• Supports distributed access to code repository
• bewildering array of access methods/security
  issues
• rsh - no longer allowed at SLAC
• pserver -
• needs custom server,
• passes weakly encrypted passwords over network
• ssh
• doesnt work with all CVS clients
• complex to set up client
• no AFS token support

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CVS vs. Sourcesafe
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Is CVS sufficient for a physics collaboration?

• If using Java - probably
• If using C, not really,
• Need to be able to switch between configurations
  easily
• Logical names where are you?
• Location of external dependencies
• Would like to use pre-built dlls where possible.
• Want to isolate users from system dependencies as
  far as possible.
• Want to avoid nightly builds
• Need to layer tool on top of CVS, make
• LCD Solution
• Development Environment Controller (DEC)

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Development Environment Controller

• Written for LCD by Tony Waite, could be used by
  others
• Hides details of file organization from user
• User deals with subsystems, Gismo, Recon, etc.
• Easy to switch between PROD,DEV,Test version of
  each subsystem
• User Profiles allow saving/restoring environment.
• Hides machine dependencies of BUILD operation
• Automatically archives CVS version numbers for
  production BUILDs

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Running a (Java) Data Server on NT
Remote Data
Desktop Client
Network Data Server
DIM

• Use NT Service Manager to Run Data Server
• Microsoft Java has built-in support for running
  as NT server
• Application can be distributed as a single .exe
  which installs itself as an NT service
• Other Java implementations can be run as an NT
  service with 3rd party add-ons (or roll your
  own).
• Error logging using NT event log/viewer

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NT Service - Pros and Cons

• Pros
• Auto start on reboot
• Runs in background
• Use service manager to start/stop service
• Real life problems
• Does not auto restart
• Application can unexpectedly pop up dialog box!
• Remote control difficult
• Remote Server Manager only distributed with NT
  server (or with NT resource kit).
• Requires port 137/138 access (blocked at SLAC
  firewall) or VPN/PPTP

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Net Meeting for Remote Control

• Netmeeting 3.0 has Remote Desktop Feature
• If run on server allows remote access to server
  desktop from any NT/95/98 machine.
• Free!
• Security
• Claims to use encrypted communication channel
• Requires NT login to access remote desktop
• Security dubious
• Potentially very useful, perhaps worth considering

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NT Disk Cache Problem

• Problem with reading large datasets
• NT will grow disk cache until it takes 99.5 of
  physical memory, regardless of who/what else
  requires memory.
• Reading large datasets can result in NT totally
  grinding to a halt.
• No system parameter to limit disk cache size
• Workarounds
• If you have access to call to C open statement
  you can turn off disk caching (big if)
• Can run program which constantly flushes disk
  cache
• Conclusion
• NT not ready for primetime data server
  applications
• Windows 2000 better?

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Things I didnt talk about

• Because I dont know anything about them
• Sniff - Cross platform IDE
• http//www.takefive.com/
• Cross platform GUI development with C
• QT Widgets
• http//www.troll.no/
• Libtool/configure
• NT ports exist but not for non-experts
• cygwin
• Unix environment under NT

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Conclusions

• Tools for code development under NT only are
  great
• Development tools probably better than Unix
• Cross platform development
• In C is a lot of extra work
• Java can make things much easier, especially for
• GUI applications
• Client/Server applications
• NT for HEP batch/server side data processing
• No obvious advantage over Unix/Linux
• Tools and OS not as well suited to task as Unix
• NT still maintains lead as desktop machine
• Unix seems to be catching up fast (gnome,
  office)