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ISO 9000 does not guarantee that the product will accomplish what a Trader
needs. I have pulled the following from the Universal Server SDK doc. Yes
the Universal Server seemed to me to be a reasonable thing to hook up to.
However considering the problems it has with the way the bid/ask is handled,
this server as it is will not be of great real time value. If the server
receives a new bid/ask the data then just sets there until it is polled on a
timed interval. By using the tick pump method to solve this problem there
are other trade offs. If a programmer used this method in hooking up to the
Universal server then the thing would be slower than Hog Station. Again only
serious traders who use a product themselves can be relied upon to produce a
product that will perform the way it should. Even this however does not
guarantee that
Read this from the Uniserv API> The reason that the timer method is
recommended is that the tick pump requires the user to look at ticks for
every symbol, not just the ticks for the symbols the user is interested in.
So to sum up you have a choice with the Universal server to either poll data
on a timed interval (the Omega Choice also I will add - and which Universal
server themselves say the following > most probably individual bid/ask ticks
will be lost. ) or push the data out. The latter of which only the entire
data base can be pushed, which will cause the server to be slower than dirt.
The proper way to do these are not any of the above. But rather a
modification of the latter we call it "selective push". mb
Below is from the Universal Server SDK ===================
The only way to get bid/ask info is to poll every symbol and check for
changes. It will show the latest bid/ask for a symbol but most probably
individual bid/ask ticks will be lost.
Page 15:
"The recommended and system efficient method of determining if a change has
occurred to the either a COMMON or OPTION structure is to maintain an
application timer. The timer can check for changes to these structures using
the last update time every 1, 2, 3 or more seconds as required by the
application. The code fragment below shows the checking for real-time
updates under the WM_TIMER message."
"Another method for determining updates is to use the UsStartTickPump and
UsStopTickPump functions described later in this document.
The tick pump informs a programmer supplied call-back function every time a
tick occurs. The reason that the timer method is recommended is that the
tick pump requires the user to look at ticks for every symbol, not just the
ticks for the symbols the user is interested in. Another problem of using
the tick pump is that it does not inform the programmer of changes to bid,
ask or information other than new trades. For these reasons, it is more
efficient to use the timer method in most cases."
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