We have detected your current browser version is not the latest one. Xilinx.com uses the latest web technologies to bring you the best online experience possible. Please upgrade to a Xilinx.com supported browser:Chrome, Firefox, Internet Explorer 11, Safari. Thank you!

Showing results for 
Search instead for 
Did you mean: 
Newbie rdickerson
Registered: ‎05-02-2010

multithreaded performance

There are some posts last year (when 11.1 came out) about trying to get PAR to use multiple threads and processor cores.  Has it improved any in the intervening updates?  Will 12.1 support multithreading in Windows?  I'm getting ready to purchase a new build machine, and need some more information so I know what's best to buy.

0 Kudos
4 Replies
Xilinx Employee
Xilinx Employee
Registered: ‎07-01-2008

Re: multithreaded performance

In 11.1 multi-threading is limited to the global placment phase (X.8) of MAP and then only 2 processors. In 12.1 multi-threading will be supported by the router. For both place and route, the 12.1 support will be able to use up to 4 processors. This will be supported on Windows. All of this applies only to the newer architectures (V5,V6,S6).


No messages are printed to indicate that multi-threading is active in 11.1. That has been corrected for 12.1.


An alternative approach to multi-tasking is to use SmartXplorer to run multiple concurrent passes. This can be done using multiple cores on one machine as well as multiple machines.

Registered: ‎06-09-2010

Re: multithreaded performance

I'm trying to enable multithreading on my ISE v12.1, but the appropriate check boxes in the MAP & PAR properties windows are greyed out? Any idea why this happens? What's more is there any way to speed up the synthesis process. I have a design that almost fills a V5 LX330T device and it takes ages to synthesize, map & par.
0 Kudos
Xilinx Employee
Xilinx Employee
Registered: ‎10-12-2009

Re: multithreaded performance

The boxes will be available in 12.2. Until then, you can select 'Minimum Runtimes' under 'Project - Design Goals and Strategies' which turns on multi-threading or run at the command line




0 Kudos
Visitor davemac22
Registered: ‎12-17-2009

Re: multithreaded performance

So is there some PAR performance improvement numbers for multi-threading on V5 and V6 large designs?  As the previous poster mentioned,  it takes a long time (~5-6 hrs for me) on a large Virtex 5 design to do PAR with ISE 11.1.  So:


1.  How good is the multithreading in 12.1?


2. How sensitive is PAR to L2/L3 cache sizes, raw CPU speed, disk or memory speeds of the host system?  Has Xilinx done any host system benchmark testing for their tools?


3. Does 12.1 improve the use of MT in the MAP algorithms over the 11.x MAP MT use?




dave mc




0 Kudos