D3 Linux vs. D3 Windows

Is there any advantage or disadvantage to going from D3 Linux to D3
Windows?


Thanks,
Danny

I might be forgetting something but here's my view:

Both platforms are equally capable but D3 NT (Windows) does support
RPC calls which are not supported in *nix.  This is only of value if
you're using the D3 Class Library, which IMO shouldn't be used anymore
now that there are much more capable connectivity solutions available.

For personal use it can't be easier to use D3NT right on the same
system you use for everything else - no need to fire up a separate
box/OS just for the database.

Many sites have migrated from D3 NT to D3 Linux for reasons including
the following:
- stability
- conflicts between the VME and FSI
- indexing issues in the FSI
- file pointer caching issues in the FSI
- frame loss in the VME
- issues with sockets

I believe D3NT v7.5 addresses some or all of these concerns, so the
choice of platform is largely philosophical or dependent on your
site-specific needs.

D3 Linux also supports rebuilding the D3 executable to include custom
functionality (linking in new functionality into BASIC, much like is
done in jBASE or OpenQM).  D3NT technically supports this as well but
I don't think anyone does it.  There isn't enough documentation or
warm fuzzies to feel good about doing this sort of thing.  If anyone
has done this with D3NT I'd like to trade notes.

D3 *nix also supports user-written assembler modes.  I've seen docs
that make it seem like D3NT could as well but I don't know anyone who
has done this successfully.  Mark?


Does that help?
T

Thanks Tony.  What about performance?  Which O/S would help D3 achieve
better performance?





<snip>

I haven't compared platform performance in years.  No DBMS operates in
a vacuum.  Factors that affect performance include:
-CPU
-RAM allocation
-whether you're running D3 Linux in the file system or in raw volumes
-disk fragmentation in NT
-other OS services and user activities running in addition to D3

All things being equal, my instinct says D3Linux would be a faster
platform.  Then again, I don't know if there are optimizations that
I'm unaware of which would allow D3NT to run faster over Win2003.  I
tend to think of D3NT as being a platform of convenience because it's
on the same system as many Windows utilities that I tend to integrate
with, and I don't need to have another OS running just to support the
DBMS.  D3NT can be upgraded on the same OS year after year without
changing the OS, whereas D3Linux is built over specific kernels so the
OS must be completely reinstalled on an almost yearly basis - that's
painful.

Let's back up.  What is it that you need to do?
- Are you doing development on a PC?
- Are you supporting a local office of 20 users?
- Are you supporting an extranet with 200 users?
- Are you supporting an internet site with hundreds or thousands of
people requiring near simultaneous access?
- Do you find yourself creating and deleting a lot of ad-hoc files and
accounts or is the environment fairly stable.
- How much data in GB are we talking about?
- Do you write communications tools in C, VB, Perl, or other
languages?
- Are you philosophically a Linux guy?  Do you prefer Apache to IIS or
have any other political reasons to swing toward one platform or away
fom another?  This is quite often the determining factor, not the
technology itself.

It's always better to approach technology from the business
perspective.  It's like a carpenter saying he needs to secure two
beams of a given width - this is a business statement.  Compare that
to "which is better, nails, staples, or glue?"  The same applies for
choice of languages, web tools, etc..  (Sorry Chandru) Choose the tool
that suits the job that you're going to do.

These articles may be of interest:
http:// 
removethisNebula-RnD.com
/blog/tech/2006/01/is-linux-really-superior.html
and 
/blog/tech/2006/02/linux-and-net.html


Any of that help?
T

What is the motivation for even considering such a move?

I'd stay with D3/Linux EVERY time! Whilst D3/Windows 7.5 may address
some issues in the future, today D3/Windows lacks features like
transaction logging, indices don't work properly in the FSI, the FSI
appears to be "fragile", programs can behave differently in the VME &
FSI, OSFI has "problems" that don't exist in D3/Linux, the "limited"
monitoring capabilities of D3 are even further linited on D3/Windows
... the list goes on.

I recently visited a site where I had to reboot their D3/Linux server -
uptime was 1473 days ! Tell me again why you are contemplating this
move?

I agree Ross. I have can only think of 3 reasons to take down a
D3/Linux system.

1. Failed Hardware - Tape, CD-RW, NIC replacement.
2. Moving the system.
3. Hurricane (And this is just a precaution) as they usually come
through just fine if they aren't soggy and don't smell like smoke.

A couple years back I think Count D. said they had to move away from
Windows because the people in charge of the system liked to load DOOM
so they could play after hours . Not a pleasant thought. To the inept
at least they will respect Linux as a *Server*. Not as likely true for
a Windows machine.

My 2, Patrick <;=)

Ross,


1. Standardizing on one O/S.
2. Reduce or eliminate the need for multi-platform training.
3. To gain confidence that the system is under control.

For instance, right now I need to expand the size of the D3 file system
(database?) which will require me to use a utility that I have very
little experience.  I believe the command in Linux is divvy, but it was
been about 3 years since I did it last.  My uneasiness is that if I
screw it up, I don't know if I can recover.  I have backups, but I've
never done a restore from scratch.  I guess I should just grab a
machine and throw Linux on it and try a restore, but the problem with
this is that I don't have a macine with an identical configuration.  I
guess this points out the need to buy two servers, albeit with less
disk and redundancy for the second one, when one buys a new server so
that a suitable test environment exists.

I would hire a D3 expert, but I don't know where to find one locally
(Dallas, TX).

So you see, if I was on Windows, I don't think my concerns above would
be an issue.


Regards,
Danny

 Install an additional drive, create a partition and mark it as type "d3" 
using fdisk. Then, add another disk statement to the pick0 file. Shutdown 
D3, reload, and *poof* you have more storage. You don't need to reload D3 or 
perform any kind of Linux magical madness. An easier way would be to re-run 
the D3_Setup application that should still be on your box. Go into the disk 
menu and add an existing parition. You should shut D3 down before you do 
that, though. If you want help doing the manual edit, post your current 
/usr/lib/pick/pick0 here and the size of the drive you want to add.


Glen 

Thanks, but I believe there is some unused (unallocated) disk space in
the current configuration.

# df -k
Filesystem           1k-blocks      Used Available Use% Mounted on
/dev/sda6              8064272   2632372   5022248  35% /
/dev/sda2                46668      3868     40391   9% /boot
/dev/sda5              7060276   6305364    396264  95% /u

This is everything that is in use.  I don't know how to tell about
unused space.

# fdisk -l

Disk /dev/sda: 255 heads, 63 sectors, 8841 cylinders
Units = cylinders of 16065 * 512 bytes

   Device Boot    Start       End    Blocks   Id  System
/dev/sda1             1         4     32098+  de  Dell Utility
/dev/sda2   *         5        10     48195   83  Linux
/dev/sda3            11      8841  70935007+   5  Extended
/dev/sda5            11       903   7172991   83  Linux
/dev/sda6           904      1923   8193118+  83  Linux
/dev/sda7          1924      2178   2048256   82  Linux swap
/dev/sda8          2179      3326   9221278+  d3  Unknown

If I understand this correctly, I have 7 partitions defined.  I think I
have 3 hard drives in a RAID 5 configuration.  Each drive is 36 GB, so
that gives a total usuable space of 72 GB, right?

Here's my pick0 file:
# /usr/lib/pick/pick0
#
# Copyright (c) PICK Systems 2001. All rights reserved
# Fri, February 13, 2004
#
name LEW
nice 0
user pick
core 1500000 10
npibs 128
nphts 32
basic 8192
brkchr 1c
escchr 1b
absbase 18
abssize 708
abslock on
blkfid 2
flush 10
dwqnum 256
disk /dev/sda8 0 9221278 # disk 0
tape /dev/fd0H1440 500 f lq  # tape 0
tape /dev/fd0H720 500 f ld  # tape 1
tape /dev/nst0 16384 d ls  # tape 2
tape /usr/lib/pick/ab 500 p lx  # tape 3
tape /usr/lib/pick/dt 500 p lx  # tape 4
tape /D3install/patch 500 f lx  # tape 5
tape /u/backups/bkup1 1000000 p lx  # tape 6
tape /u/backups/bkup2 1000000 p lx  # tape 7
tape /u/backups/bkup3 1000000 p lx  # tape 8
tape /u/backups/bkup4 1000000 p lx  # tape 9
tape /u/backups/bkup5 1000000 p lx  # tape 10





<snip>
<snip>

 Yes. Usable RAID5 space = total of all drives of same size minus the size 
of one drive. It looks like you have sda8 assigned to D3. sda2, sda5, and 
sda6 are all ext2 or ext3 file systems mounted to Linux. You have a virtual 
sda3 parition split into 5,6,7, and 8 logicals. You have no free space to 
add to D3. If you need more space, you will need to:

A)  Review your RAID controller manual and determine if you can add a new 
drive to the array without rebuilding it. Most hardware RAID controllers 
will allow this with no headache at all. Just plug it, boot it, and go into 
the RAID BIOS config. Normally, you can select the new drive and choose to 
add it to an existing array. That's it. Some controllers will want to 
re-stripe the array before you reboot. Others will do it in the background 
automatically, as long as you don't power the machine off.

B) add another pair of drives, if you have space on the controller and set 
them up as RAID0. Then you can just add that array (sda9 or sda10 probably) 
to D3 as a new disk statement without touching the existing Linux install.

C) Just add an IDE or SATA drive and move /u to that new partition. I don't 
know what's on /u so I'm assuming it's not critical. If it is, you're back 
to A. If it's not, you can re-use sda5 as a new partition for D3.

 Keep in mind that if you add a drive larger than 36GB to your existing 
array, you will only get 36GB out of it. RAID5 requires identical drive 
sizes and the controller will typically enforce that, regardless of the real 
drive geometry. If you need 80GB more storage, then you will need to add 3 
more 36GB drives.

Glen 

<grumble>  I should have done the math. You have 44GB free in sda3 for 
logicals. You don't need to do any of what I posted. :P Well.. that is if 
44GB is enough space for D3.  Just add a new parition(s) using fdisk and tag 
it/them type "d3". I don't setup partitions larger than 2GB for D3, but 
yours looks to have a 9GB partition already. If you want me to do it, I'll 
need an SSH login to the box and root access.

nojunk_glen@"mvdevcentral dot com"

Glen