Review of pwlconfig 0.90

[Dennis W. Tokarski]

Hi Ralph,

Sorry it took me so long to get back to you with a review of pwlconfig
0.90. I got sidetracked for a bit in the "educational" experience of
seeing what a minimal boot disk really requires if constructed manually.
It was really rather interesting, and I at least wound up with something
useable for my initial target/development system.

I hope you find this feedback helpful.

  --Dennis

 ====================================

As a general observation, the way pwlconfig drops into a text mode
screen between menus creats a disconcerting flash. Even doing so for
the sake of printing progress dots is kind of annoying. Painting one
menu directly after another would be preferable. Progress indicators
for long operations would be nicer if shown on the menu display as
a spinning arrow, or a %done display, or even the more typical
%done "thermometer" style progress bar.

Here are some other rough spots I ran into, pretty much in the order
they'd pop up when creating a new project.

* When pwlconfig is started for the very first time (i.e., its
  .* files don't exist yet and there is no "projects" directory),
  it asks for a project to create but not a target device.

* After the first run, creating a new project does prompt for a
  default device, (DOC/FLOPPY/etc) which MUST be entered in upper
  case. This should probably be made lower case, case insensitive,
  or selected from a menu of fixed choices.

  Currently, a mistake on entry gives a warning, but no reprompt.
  Setting the device must then be done by manually selecting
  Manage Projects/Project defaults/Device Type, then editing the
  field.

* When a target device is correctly entered for a newly created
  project, it appears nothing is done with that information. A
  look at project defaults shows they're all set to assume Flash.

* Modifying the device type in the Reset Project Defaults menu
  doesn't cause coordinated changes to other fields, like Boot Location,
  Device Name, Device Partition, and Device Type Node. Reasonable
defaults
  could be supplied keyed to the selection of Device Type.

* If a project is removed, the pwlconfig is pretty good about
  insisting that the user select another project. However, it
  is possible to exit the whole program suite without doing so.
  Upon restart, pwlconfig reinserts the removed project name into
  the projects list under Manage Projects, but it has new
  default configuration information.

  Essentially, pwlconfig implicitly creates a new project using the  
  same name as the project the user just removed. This is potentially
  confusing. Probably the right thing to do is not have a current
project
  and go back to insisting the user select one.

* When configuring the file system the base-filesys-2 package
  has a *lot* of possibly extraneous stuff in the dev directory.
  So does base-filesys-minimal-1, for that matter. When pruning this
  collection by manually deselecting individual items, each deselect
  causes a drop to text mode while pwlconfig prints out about three
  and a half lines of progress dots, which takes a looooooong time.

  This one *really* had me climbing the wall. I finally took to just
  accepting the whole smash, generating the file system, then using
  'rm' to clean out the directlry after stopping pwlconfig.

  It would be much much much ***much*** nicer to simply note the
  selections/deselections and defer whatever processing is neccessary
  until after the menu is exited. Or maybe an "Apply" button would be
  appropriate here?

* Here's a problem which showed up while trying to use one of the
  "minimal" packages, busybox-0.36. Suppose you really want to
  use busybox along with some other package which contains a
  conflicting file. You can't install the other package second
  because it might replace some of busybox's links with real files,
  and thus take up more space than you want. But installing busybox
  second doesn't work either, because the "ln" command to make the
  links is issued without the -f option.

pwlconfig appears to assume that the target device will be mounted
as / in the running system. There is no provision for use of initrd
or compressed ram disk. These features really are needed if the goal
is to make some sort of minimal special purpose rescue/diagnostic
disk. At the very least, separate boot and root floppies need to
be supported.

As a result, pwlconfig can't presently make a bootable floppy at
all. There are several obstacles:

 * For one, the libraries are too darn big, and there's nothing
   we can reasonably do about it. They either *must* go on a
   compressed ram disk or there has to be a separate root floppy.

 * There are too many entries in /dev taking up too many inodes.
   When pwlconfig copies the project filesystem to the floppy,
   it quickly gets a "no space on device" error even if
   there's plenty of space. What's really happening is it's
   out of inodes. You need to make the file system with something
   like
         mke2fs -N `wc -l ./projects/PROJECTNAME/mnt` /dev/fd0

   Presently, just the base filesystem package is too much for
   a floppy made with just "mke2fs /dev/fd0".

 * Making the floppy boot able with LILO has a couple of hitches--  
   pwlconfig insists that lilo be in ./bin, rather than just using
   /sbin/lilo as installed, and (cosmetic only) the prompt for using
   the existing lilo.conf.FLOPPY is done in text mode.

 * The generated lilo.conf.FLOPPY file expects a kernel image name
   of vmlinuz, but the kernel packages use bzImage.

Just to see if a floppy produced by pwlconfig would boot, I made one up
without any libraries. After resolving the above problems, lilo seemed
to run successfully. However, trying to boot the floppy resulted in the
first stage loader stopping after printing "L", then it loops printing
an error code: "04". Removing the "disk=" line from lilo.conf.FLOPPY
solved this problem. 



      *** Some suggestions for initrd/ramdisk/root disk support ***

It seems that a natural way to extend pwlconfig would be to split
the Configure Project File System menu into three sections: Configure
Boot File System, Configure Initrd, and Configure Root File System.
In the latter case there should be options to specify if the Root
File System will be a ramdisk, and if it should be compressed. You
would also need to specify the ramword parameters. Ramdisk size could
be determined automatically using du.

Each of these three options would build file systems under separate
trees: ./projects/PROJECTNAME/{boot,initrd,root} using the current
package installation procedures. The mere existence of the initrd
and/or root file trees at the end of the procedure would be enough
information for you to figure out how to generate the composite
boot disk, or boot/root set.
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