( ESNUG 472 Item 5 ) -------------------------------------------- [04/30/08]
Subject: One user on IC Manage vs. Synchronicity with a Cadence interface
> If you have weirdly strong feelings about HW data manangement SW, email
> it to me.
From: Clint Meyer <clint.meyer=user domain=nsc not mom>
Hi, John,
We have been using IC Manage to manage our design and library data for 2
years. We are a small (under 20 people) remote design center in western NY
working for a Silicon Valley-based semiconductor house. We are a typical
design center - understaffed and overworked, constantly worried about our
jobs and trying to impress the mother ship. We design column drivers for
mobile LCD displays. These chips are incredibly complex. They typically
have a large die size with aspect ratios as high as 20:1, a block of RAM,
power supplies with a range of 25v, as many as 500 analog outputs, and many
other customer specific analog blocks. We are currently designing in a
deep submicron process.
While most of the design for these devices is done on site we are also
forced to use off site circuit and layout designers to fill in the holes in
lieu of hiring. During our typical 9 month project cycle our design team
grows by 50% across multiple sites. We typically have to coordinate circuit
and layout design, both full custom and RTL across as many as 4 sites in as
many corners of the US. Due to the large aspect ratio and the inherent
relationship between all of the blocks on our chips, effective communication
between the entire team on a semi-daily basis is mandatory.
IC Manage's fundamental capabilities are:
- Enabling multi-site sharing of day in and day out design data
- Simplifying project management, through its ability to archive and
control permissions and ensure that the version our designers want
to use is the one they are in fact using.
With IC Manage we were able to do trickier things that let us cut a project
cycle by 1 month out of 8 months, or about 12%.
Before we had IC Manage, we used to change the name of the library to a new
revision after a tape out and our designers would spend time updating
simulation test benches when the library names change -- all these things
are prone to errors. Because IC Manage manages the files and knows their
context (e.g. library names and workspace locations), file system naming is
not required, particular when creating new projects. Previously we needed
to continuously rename files, but IC Manage is name space independent and
automatically tracks this information for us, so our designers are able to
use the same library for multiple tape-outs for the same IP block and we
save time because everything stays the same even after tape-out. The rev
is nested inside IC Manage, allowing us to maintain the same library names,
cell names, workspace areas. Just rely on rev control to go back in time.
Before we had IC Manage, it typically required the combined equivalent of
80% of a full-time person to ensuring data integrity for multiple sites on
one project. Our designers would have to rsync or FTP files back and
forth, a lot of time was spent tarring and unzipping files. There was no
real-time interaction with the design data and we wasted a lot of time
manually updating local copies and transferring and trying to sync up files.
With no common database or central design management system, there were lots
of opportunities for errors and downtime while transferring files and
synching up manually. Our designers each spent about 30 minutes a day just
dealing with those issues.
IC Manage significantly improved our cross site design collaboration with
only a few modifications in our daily activity. We were able to do more
work in less time because we weren't futzing around with getting data back
and forth -- untarring and unzipping files -- and making sure everyone was
on the correct most up to date version.
Even with IC Manage, design management still requires some savvy and
discipline: Designers still need to look at visual references and
understand what they mean, they can't just ignore it or there is still
potential to be out of sync. We must maintain and implement flow controls
over data in our organization. We put a data management discipline into our
flow and changed how we taped out.
Cadence Interface: IC Manage vs. Synchronicity
At a previous job (again a remote design center), my company used
Synchronicity to manage our Cadence data. My new company had actively
evaluated both software and chose IC Manage as its DDM (design data
management) solution.
Both Synchronicity and IC Manage have Cadence-specific front ends to them.
They both work like any other version control software in that they have a
central repository of data from which local copies are made for each user
whose permissions are controlled and forced to be in sync with the central
depot. Every full custom designer starts his day through the library
manager GUI. For a DDM tool to work in the full custom design flow, it
needs to control permissions of each file, by intercepting the normal GUI
based user operations.
Having used both Synchronicity and IC Manage, I much prefer the IC Manage
library browser because:
1. Synchronicity keeps the stock Cadence library manager, while IC Manage
has created their own, and it is a significant improvement over the
stock Cadence one. Not only are we able to perform every function as
before, it gives us a host of new and important information without
having go to a properties window. With subtle visual cues we can
easily see who has what cell open, what version we have on our
local copy of the database.
2. With IC Manage, we can quickly and easily go back in time to an older
version, check something in/out, make a local only copy, etc. - which
is a very big thing. With Synchronicity, we couldn't go back in
time without a lot of hassle.
3. With IC Manage, every one of these actions is bound to a keystroke.
This seems like a minor item, but it saves me a lot of time not having
to take my hand from the keyboard. I can move quickly to perform
multiple different actions to many different files.
4. IC Manage's data management is so well-integrated that it is generally
unnoticeable, e.g. it automatically updates the prop.xx file and puts
it on the server. It also provides complete version and icon-based
state notification. We can more easily and quickly reuse data and get
a simulation going because we can easily assemble the correct data sets.
5. Synchronicity wasn't nearly as seamless as IC Manage. The Synchronicity
library manager didn't give useful info -- I had to use command lines to
get even the most basic information. It was clunky and bare bones on
features. From what I have heard, Synchronicity has not changed and is
still doing just basic version control.
Distributed Design and Bandwidth Use:
Full custom circuit and layout design is graphically intensive. MXS circuit
and layout designers interact with the project through the library manager.
Through the GUI we gain write/read access to each cell located on the chip.
Before we had IC Manage, the graphic intensity of our work prevented us from
putting our projects on the WAN as it brought work to a standstill. We
tried other options from rsync to ftp, however they were all error prone and
time consuming. The primary function we wanted out of our DDM solution was
local access to remote data. We needed the speed of LAN, but on a common
library.
If you're a remote site like we are, I would advise you to have IC Manage
installed on a local server or have a fast internet connection.
IC Manage is a graphically-based program like Cadence's library manager. We
are a remote site and have been using IC Manage on a server that is 2000
miles away instead of a local server. Because we don't have a very fast
internet - just a T1 - it takes us 8-9 seconds to ship files back and forth
instead of 1 second for a faster connection. Those speed problems go away
on local server or with a faster connection. IC Manage will push the
boundaries of a T1 when used in conjunction with all the other activity the
design center.
We have 8 people in this design center using IC Manage. IC Manage has a
proxy server, which will send a copy of the database over the network just
to the remote proxy. Now when a user syncs to the latest copy it is local.
This significantly increases speed as the syncing of data over the WAN is
done once by the proxy, and then local users sync to the local proxy. This
minimizes network traffic/bandwidth usage and speed. This is a good step
(free)in lieu of getting a local server license. This won't make checking
in new data any faster, but will significantly speed up the syncing of data.
Project Management:
IC Manage has a robust behind-the-scenes project management system and
workflow. We can do almost anything we want with IP libraries; branch them,
go back in time, or access multiple versions at a time. For example, if we
make a change to a reusable IP block, IC Manage's project management system
lets us choose whether or not to propagate the change to other projects
using the block. This allows us to change our approach depending on the
situation.
Over the last 2 years of using IC Manage, we have taped out more than a
dozen different devices ranging from test to full production. While it was
not the main reason for using IC Manage initially, we have gotten
significant mileage out of IC Manages revision control, release and
configuration management functions, project setup features and command line
interactivity. While revision control and configuration management is
common place and relatively easy when dealing with text files, it is rarely
used when dealing with Cadence design files. Our biggest hurdle was
convincing people of the value in a new system when they already have
semi-manual solutions in place (no matter how inefficient and mistake prone
those solutions were).
Another huge benefit of IC Manage is that the project set-up took me less
than an hour and there is virtually no ongoing support needed for the
project data once it is set up. I can have different configurations for
different users, different sites, and different groups of people. It allows
me a level of control that I have not had before. This allows me to get
back to my real job with as little time lost as possible. And once everyone
is up and going there have been months that go by without a single problem;
I can't stress enough how important that is to us. We needed a DDM solution
that solved our multi-site design problems without interfering with the
design work. IC Manage delivered better than I had expected. As we use IC
Manage we find there is more and more we can do with it - it is flexible
enough to give version control of any file, not just a Cadence file, e.g.
synthesis, digital libraries, text files, and coding.
- Clint Meyer
National Semiconductor Rochester, NY
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