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About new Salvo 2 release

PostPosted: Fri Nov 24, 2000 7:27 am
by luben
Hello, I saw that you make new release with array based constant time behavior, or something like that.

Would you mind to explain in more details what you mean?

By the way if I buy the one year renewal version and the year expiered, could I still use the files? Or I just can't receive support. In fact I see that you have really excellent support on the forum. If I receive answers to my questions, what I could expect more.....

I already asked your stuff about one offer for academic priceing.

Have you a nice weekend.
Best Regards
Luben Christov

Re: About new Salvo 2 release

PostPosted: Sat Nov 25, 2000 12:31 pm
by Salvo Tech Support
The next release of Salvo, version 2.2, is scheduled for January-February 2001.

This version will include priority-array-based operation as a configuration option.

Currently, Salvo uses priority queues to manage tasks and events. The advantage is that priority queues are very memory-efficient. The disadvantage is that the time to execute certain Salvo functions (as outlined in Chapter 8 Performance of the User Manual) is not constant, but rather is dependent on the number of tasks. Computing the worst-case time that interrupts are disabled can be quite complicated ... Chapter 8 has more information.

When compiled for array mode, Salvo's run-time behavior becomes constant-time. That means that each Salvo service completes in an amount of time that is independent of the number of tasks. In array mode, for up to 8 tasks, this time is roughly equal to the queue-based time for n=3 tasks. This means that for only 1-2 tasks, queues will be faster. More more than 2 tasks, arrays will be faster, and arrays are always constant-time.

Note: with arrays, tasks cannot share priorities -- every task must have a unique priority. This means that tasks cannot round-robin at the same priority.

In most cases, array mode and queue mode use the same amount of ROM and RAM. Only on systems with large numbers of events does array mode use more RAM than queue mode.

The freeware libraries will remain in queue mode only. Array mode will only be available to users who have purchased the full version of Salvo.

After your one-year susbscription expires, you may continue to use Salvo. You will not receive priority tech support, but you can continue to use the web site, etc. You can later purchase a subscription renewal, which will entitle you to upgrade to the latest version, plus another term of priority support.