( ESNUG 376 Item 11 ) ------------------------------------------- [08/29/01]
Subject: ( DAC 01 #14 ) Cooley Shouldn't Help Spread Distorted Specman FUD
> I know and like Janick. He's a good guy. In my gut I don't think he
> cooked the numbers in his survey -- and, more importantly, even though
> I didn't do a count in my DAC trip report survey data, I did remember
> more pro-Specman user e-mails than pro-Vera users e-mails.
From: Chris Spear <spear@synopsys.com>
John,
Before anyone else quotes Janick's "survey" on testbenches, look at the
responses on his web site. A very telling quote was #258:
"258. Specman
I answered the survey despite the two phone calls and one email
from Verisity guys trying to get me to answer this to up their stats."
How about a less biased survey? How about what skills are employers
looking for? Like your Missing Elf analysis, I searched the jobsite
http://www.dice.com for "verisity or specman" and came up with 80 entries.
"Vera" turned up 158 entires. Next, try the big one, Monster.com, gave
48 Vera jobs and 37 "verisity or specman" jobs.
In fact the first Specman hit was for Stratus which switched from Specman
to Vera last year, but must have forgotten to tell their recruiter.
Of course now the Verisity marketing people will call all their customers
telling them to spice up their job postings to create the proper bias.
Will it ever end?
- Chris Spear
Synopsys Marlboro, MA
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From: "Faisal Haque" <fhaque@cisco.com>
John,
As far your question about Functional Verification Languages the two I am
experienced with are Specman and Vera. Majority of the people I am familiar
with are using Vera and some are using Specman. I don't know anyone using
Rave.
Both Vera and Specman have their trade-offs. For these two tools:
1) Performance. I give Vera the edge here. Specman does not work with
Save/Restore in VCS. But both tools need to improve in this area.
2) Ease of Learning. Definitely give a huge edge to Vera. Whereas Vera
is very similar to traditional languages such as C++ and Verilog,
Specman has its own unique, non-intuitive lexicon. This I think is
its biggest weakness. Learning curve for Vera is in weeks whereas
learning curve for Specman is in months. Feature wise they are both
powerful and very comparable.
3) Support for Concurrency. Give Vera an edge here, too. It has more
built-in concurrency constructs which are more generic and therefore
more widely applicable.
4) Test case generation efficiency. Specman gets the edge here because
of its more powerful recursive constraint solver.
5) Testbench creation efficiency. Vera gets an edge here. This is due to
longer debug cycles, because of the non-intuitive nature of Specman.
6) Temporal expressions. They appear to be even. Vera has recently added
support for temporal expressions. However, Vera's syntax appears to be
more intuitive.
7) Third party support. Vera has a slight edge because it seems to have
more support from third party waveform viewers.
8) Code Reuse. Vera has the edge here because of the virutalized RTL
interface capabilities, also the more structured object oriented
paradigm is easier to maintain in a large collaborative environment.
Because Vera seems to be the better language, Khizar Khan (of Sun), Jonathan
Michelson and myself (both Cisco), chose to write a book, "Art of Verification
with VERA".
- Faisal Haque
Cisco Systems
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