TweetFollow Us on Twitter

Fine Tune MPW
Volume Number:6
Issue Number:7
Column Tag:Mac Workshop

Fine Tuning Code With MPW

By Allen Stenger, Gardena, CA

Tuning with MPW

[Allen Stenger works on the F-15 radar software for Hughes Aircraft Co. His technical interests are software reliability, computer architecture, and computer languages. Programming the Macintosh has been his hobby for the past five years.]

The Macintosh Programmer’s Workshop documentation does a good job of describing how to use the performance analysis tools, but it does not explain what to do with the results. This article is a tutorial on how to tune a program with MPW, using the performance reports as a guide to which areas of the program are most in need of improvement.

For the example program we will use a dragon-curve drawer. This is an example in the Smalltalk books, and Listing 1 is a straightforward translation of the Smalltalk-80 program into SemperSoft Modula-2. This straightforward program takes about 8 seconds (477 ticks) to draw the dragon. This is not extremely slow, but one imagines that it could be done faster. In fact, we will be able to get a 16-times speedup with some simple transformations, and by being a little trickier we will get a 22-times speedup.

This is an artificial example, for a couple of reasons. First, for any imaginable use to which DrawDragon might be put, its present performance is adequate--there is no practical value to speeding it up. Second, the MPW tools would normally be applied to much larger programs, and are in some ways an overkill for this simple example.

Speculations

We will start out with some speculations on the causes of the slowness of the straightforward dragon. After doing the tuning we will revisit these and see how good our intuition was.

From inspecting the code, one might generate a list of possible “problem areas” such as the following:

Use of recursion. According to the folklore of programming, recursive programs are slow, and certainly the Dragon procedure seems to spend most of its time calling itself rather than doing any useful work.

Use of high-order language. Traditionally, in order to get the highest performance, one must write in assembly language. The SemperSoft compiler is a one-pass compiler, and presumably does little optimization.

Use of range-checking. This example is compiled with checks on, which in some programs can cause a significant slowdown.

Use of floating-point. This example was run on a Macintosh Plus, which has no floating-point hardware and does all floating point in software.

Graphics operations. These typically take a lot of CPU time. (There might not be much we can do about this one, since the program’s whole purpose is to draw on the screen.)

Tuning -- Preparation

We can instrument the dragon program following the recipes in the MPW manual, Chapter 14 (the method is the same regardless of language, although the interface details vary slightly). Here we will only change the calling program, DrawDragon, and leave the other modules undisturbed. Since the performance measurements are done by random sampling of the program counter, the whole program will be instrumented merely by starting the measurement at the beginning of the run and ending it at the end - it is not necessary to modify each routine. The instrumented DrawDragon module is shown in Listing 2.

The performance analyzer yields an execution “profile” of the program, characterizing it by where it spends its time. It is usually only helpful to look at the top five routines - everything below that takes such a small amount of time that, even if we could eliminate a routine totally, it would have a negligible effect on the timing. Here, on our first run, we need only look at the #1 routine, since it takes 72.6% of the time (total time for the program is 493 ticks). This is the Pack4 routine, which is not in the Dragon program -- it is the SANE floating-point routines, as may be looked up in Inside Macintosh. So our first tuning step is to reduce the amount of time spent doing floating-point work.

Tuning -- First Pass

Some people (particularly FORTH fans) advocate doing no floating point at all, but using instead scaled integer arithmetic. For most programs, eliminating floating point altogether would be a drastic operation. For our little DrawDragon program it is not so bad, but let’s see what else we could do first. Unfortunately the report does not break down the floating-point operations used, but by examining the code we see that each line drawn requires 2 integer-to-float conversions, 2 float-to-integer conversions, 3 floating-point multiplies, and 1 each sine and cosine. It seems likely that most of the floating-point time is spent on the sine and cosine, with the multiplies coming in a distant second. Further examination of the program reveals that sine and cosine are called with only 4 possible arguments (0, 90, 180, and 270 degrees), so this suggests the use of a look-up table storing the values of sine and cosine for these arguments.

Making this change and re-running the program and reports shows that this does cause a large speedup - the timing is now 86 ticks, or 5.7 times faster. The top item on the performance report is still Pack4 with 41.6%, so our next step is to try to eliminate still more floating-point operations.

Tuning -- Second Pass

After scrutinizing the improved program some more, we may remember that the reason we put in the sines and cosines in the first place was to handle drawing of lines at arbitrary angles. For the 4 angles that we actually use, the sines and cosines have integer values, so (for our particular case) there is no need for floating point anyway! We therefore make a simple re-coding of the Go procedure to do all calculations as integers. (Since the routine is now getting faster, there are not enough program-counter samples to get a good breakdown of where the time is spent, so we will also draw the dragon 10 times in a loop and divide by 10 to get the time per dragon.) Upon re-running this, we find that the time has decreased to 30 ticks (2.9 times faster), and the top 5 routines in the performance report are all QuickDraw routines and comprise 73.2% of the time. Further improvement seems to depend on inventing some way of drawing lines faster than QuickDraw can, which seems a dim hope.

Tuning -- Third Pass

Surprisingly, this is possible, in the special case we are dealing with (which has only horizontal and vertical lines). By trying some separate timing tests, it appears that our lines can be drawn in 1/3 less time by using FillRect rather than Line. Implementing this leads to a program which runs in 22 ticks (1.4 times faster), for an overall improvement over the straightforward Dragon of 22:1. This speedup requires changes to only one routine, Go. The revised Pen module is shown in Listing 3.

Speculations Inspected

The big winners among our speculations were floating point and graphics operations. Floating point took up most of the time in the original program, and by eliminating it we were able to get most of the speedup. Graphics operations take up most of the remaining time, and although we made some reduction in this, it seems unlikely that there is much more we can do. Possibly we could do something sneaky such as building the whole picture in memory without using graphics operations, then copying it to the screen with CopyBits; but this would be very complicated and perhaps not much of an improvement. (One of the hardest parts of tuning is knowing when to stop. Most programs can be improved indefinitely, but they gradually get more complicated and error-prone.)

The issue of recursion turned out to be a red herring. The total time spent in the Dragon procedure is only 3.9% of the total, and this includes the recursive calls. Recursion has a bad reputation, for two reasons. First is the bad recursion examples often given in textbooks (usually factorials or Fibonacci numbers), which can be done more simply and faster by iteration. Second, in some older languages and implementations, either there is no recursion in the language, so it must be simulated by the program (FORTRAN), or it is treated as a special case (JOVIAL, PL/I) and really is much slower because it requires a special dynamic allocation of variables rather than the normal static allocation. In more modern languages such as Pascal or Modula-2, all variables are dynamically allocated and recursive calls are no different (and therefore no slower) than other calls.

The impact of using a high-order language or of range checking varies a great deal depending on the program and on the language implementation. In this example most of the time was taken by things outside the generated code, which seems to be inherent in the particular problem being solved and not likely to be affected much by the implementation language. In the final version of the program, the Modula-2 routines take a total of only 13.3%, so re-writing in assembly or taking out the range checks could not possibly save more than this. The typical Macintosh application tends to consist mainly of calls to the Toolbox, interspersed with occasional calculations, so the timing of a tuned program tends to be dominated by the Toolbox time and does not depend greatly on the implementation language. For programs such as spreadsheets and compilers this is not true, since they really do spend a great deal of time on internal calculations, but it is true of most applications.

Conclusion

By applying the MPW performance analysis tools and making the improvements suggested by the program profile, we were able to speed up the dragon-drawer 22 times. The value of the execution profile is in telling us what not to look at. Most of a program’s execution time is spent in a few very places, and we should concentrate our efforts on those few places. (In Quality Control this is called the principle of the “vital few and the trivial many.”) Profiles are more valuable for large programs, since there is more to ignore there. In any case, success in tuning depends on measurement.

For Further Reading

Jon Louis Bentley, Writing Efficient Programs. Prentice-Hall, 1982. An excellent book on tuning; of value both to the professional programmer and the hobbyist. Our Dragon example illustrates his principles Space-For-Time Rule 2 -- Store Precomputed Results (sine and cosine tables), and Procedure Rule 2 -- Exploit Common Cases (eliminate floating-point since not needed in our case, and use FillRect for faster horizontal and vertical line drawing). He gives many other principles which we did not have a chance to use. In the beginning of the book he goes through 10 steps of optimizing an Approximate Travelling-Salesman Tour to get an overall improvement of 17:1.

Adele Goldberg and David Robson, Smalltalk-80: The Language and Its Implementation. Addison-Wesley, 1983. The source of the Dragon program (on pp. 372-3).

Donald E. Knuth, “An Empirical Study of FORTRAN Programs”, Software--Practice and Experience, v. 1 (1971), pp. 105-133. Source of the term “profile.” This article is written from the viewpoint of a compiler developer, and considers several levels of optimization which can be applied to programs. Many examples of optimization.

Mike Morton, “Faster Bitmap Rotation”. MacTutor, v. 4 (1988), no. 11, pp. 86-90 (reprinted in The Definitive MacTutor, pp. 56-60). Another example of tuning, using only the total time of the routine as a measure and yielding a speedup of 3:1. Morton was careful to measure each attempted improvement to the routine; the exact method of measurement is not important, but you must measure.

Stephen Dubin, Thomas W. Moore, and Sheel Kishore, “Using Regions in Medicine with C”. MacTutor, v. 3 (1987), no. 10, pp. 27-31 (reprinted in The Essential MacTutor, pp. 146-150). Description of re-coding a routine to calculate the area of a region from Pascal or C to assembler, yielding a 1000:1 speedup.

James Plamondon, “Finding The Area Of A Region in C” (letter). MacTutor, v. 4 (1988), no. 4 (reprinted in The Definitive MacTutor, p. 699). Criticizes the previous reference for solving the wrong problem (i.e., working very hard to get a very good estimate of the area of a region drawn freehand). Gives a faster C routine for doing a less-accurate but adequate estimate. In most applications you have some leeway in the problem you solve, and you can use this to make the solution easier and faster. We did not take advantage of this in the DrawDragon program; one speedup we might have applied is to draw the line only one pixel wide (which is about twice as fast as drawing it 4 pixels wide). Bentley (reference above) also considers this in his Approximate Travelling-Salesman Tour -- since it is only an approximate solution anyway, there is little harm in going from floating-point to slightly less accurate scaled fixed point numbers.

Source Listings

Listing 1 - Straightforward Dragon

(******************************************************)
(*   *)
(* file:  DrawDragon.m      *)
(*   *)
(* Main program to test Dragon method.   *)
(*   *)
(* Written in SemperSoft Modula-2 v.1.1.2                  *)
(*   *)
(* Allen Stenger August 1989    *)
(*   *)
(******************************************************)

MODULE DrawDragon;

FROM InOutIMPORT WriteLong, WriteString, Read;
FROM InsideMac   IMPORT TickCount;
FROM DragonModuleIMPORT Dragon;
FROM PenIMPORT Home;

VAR
 oldTime,
 newTime: LONGINT;
 ch     : CHAR;

BEGIN
 oldTime := TickCount();
 
 Home;
 Dragon( 8 );
 
 newTime := TickCount();
 WriteString( “Run time is “ );
 WriteLong( newTime - oldTime, 6 );
 WriteString( “ -- press space to exit “ );
 Read( ch );
END DrawDragon.

(******************************************************)
(*   *)
(* file:  DragonModule.d    *)
(*   *)
(* Implementation of Dragon method from                    *)
(* Goldberg and Robson,     *)
(* Smalltalk-80:  The Language and Its   *)
(*   Implementation, pp. 372-3.      *)
(*   *)
(* Written in SemperSoft Modula-2 v.1.1.2                  *)
(*   *)
(* Allen Stenger August 1989    *)
(*   *)
(******************************************************)

DEFINITION MODULE DragonModule;

PROCEDURE Dragon( order : INTEGER );

END DragonModule.

(******************************************************)
(* file:  DragonModule.m    *)
(* Dragon method - see definition module for         *)
(* description.    *)
(* Written in SemperSoft Modula-2 v.1.1.2                  *)
(* Allen Stenger August 1989    *)
(******************************************************)

IMPLEMENTATION MODULE DragonModule;

FROM PenIMPORT Go, Turn;

PROCEDURE Dragon( order : INTEGER );
BEGIN
 IF order = 0
 THEN 
 Go( 10 );
 ELSE
 IF order > 0
 THEN
 Dragon( order - 1 );
 Turn( 90 );
 Dragon( 1 - order );
 ELSE
 Dragon( -1 - order );
 Turn( -90 );
 Dragon( 1 + order );
 END; (* IF *)
 END; (* IF *)
END Dragon;

BEGIN
END DragonModule.

(******************************************************)
(* file:  Pen.d    *)
(* Implements some of the methods for the Pen class  *)
(* in Smalltalk-80.  *)
(* Written in SemperSoft Modula-2 v.1.1.2                  *)
(* Allen Stenger August 1989    *)
(******************************************************)

DEFINITION MODULE Pen;

(*
 Go in the current direction the specified distance
 (units of pixels).
*)
PROCEDURE Go( distance : CARDINAL );

(*
 Change the current direction by turning degrees 
 (positive degrees = clockwise).
*)
PROCEDURE Turn( degrees : INTEGER );

(*
 Move to original pen position.
*)
PROCEDURE Home;

END Pen.

(******************************************************)
(* file:  Pen.m    *)
(* Pen methods - see definition module for                 *)
(* descriptions.   *)
(* Written in SemperSoft Modula-2 v.1.1.2                  *)
(* Allen Stenger August 1989    *)
(******************************************************)

IMPLEMENTATION MODULE Pen;

FROM Terminal  IMPORT ClearScreen;
FROM InOutIMPORT Write;
FROM MathLib0  IMPORT sin, cos, entier, real, pi;
FROM InsideMac IMPORT Line, MoveTo, PenSize;

CONST
 DegreesToRadians = pi / 180.;
 (* conversion factor *)

VAR
 currentDegrees  : [0..359];
 (* direction we are
 facing -- 0 = right. *)

PROCEDURE Go( distance : CARDINAL );
VAR
 currentRadians  : REAL;
 realDistance  : REAL;
BEGIN
 currentRadians := DegreesToRadians 
 * real( currentDegrees );
 realDistance := real( distance );
 Line(  entier( realDistance 
 * cos( currentRadians ) ),
 entier( realDistance 
 * sin( currentRadians ) )
 );
END Go;

PROCEDURE Turn( degrees : INTEGER );
VAR
 tempDegrees:  INTEGER; 
BEGIN
 tempDegrees := INTEGER(currentDegrees) + degrees;
 DEC( tempDegrees, 360 * ( tempDegrees DIV 360 ) );
 IF tempDegrees < 0 
 THEN INC( tempDegrees, 360 );
 END; (* IF *)
 currentDegrees := tempDegrees;
END Turn;

PROCEDURE Home;
BEGIN
 MoveTo( 110, 200 );
 currentDegrees := 270; (* facing up *)
END Home;

BEGIN
 ClearScreen;
 Write( 0C );  (* graphics initialization kludge *)
 PenSize( 4, 4 );
END Pen.
Listing 2 - Instrumented DrawDragon module
(******************************************************)
(* Main program to test Dragon method.   *)
(* This version includes MPW performance analyzer    *)
(* calls.   *)
(* Written in SemperSoft Modula-2 v.1.1.2                  *)
(* Allen Stenger August 1989    *)
(******************************************************)

MODULE DrawDragon;

FROM InOutIMPORT WriteLong, WriteString, Read;
FROM InsideMac   IMPORT TickCount;
FROM PerformIMPORT InitPerf, PerfControl, 
 PerfDump, TermPerf, 
 TP2PerfGlobals;
FROM DragonModuleIMPORT Dragon;
FROM PenIMPORT Home;

VAR
 oldTime,
 newTime: LONGINT;
 ch     : CHAR;
 thePerfGlobals : TP2PerfGlobals;
 junk : BOOLEAN;

BEGIN
 (* Initialize performance measurement *)
 thePerfGlobals := NIL;
 IF InitPerf(  
 thePerfGlobals, (* measurement block *)
 20,    (* sample interval *)
 8,(* bucket size *)
 TRUE,  (* measure ROM *)
 TRUE,  (* measure application *)
 “CODE”,(* resource type to 
 measure *)
 0,(* ROM ID *)
 ‘’,    (* ROM name *)
 FALSE, (* measure RAM misses *)
 0,0,0  (* for RAM misses *)
 )
 THEN
 ELSE WriteString( “Initialization failed” );
 END; (* IF *)
 
 (* Start performance measurement *)
 junk := PerfControl( thePerfGlobals, TRUE );
 
 oldTime := TickCount();

 Home;
 Dragon( 8 );
 
 newTime := TickCount();
 
 (* End performance measurement *)
 IF 0 = PerfDump(  thePerfGlobals,
 “DrawDragon.dump”,(* dump file for 
 results *)
 FALSE, (* histograms *)
 0 (* histograms *)
 )
 THEN
 ELSE WriteString( “PerfDump failed” );
 END; (* IF *)
 TermPerf( thePerfGlobals );
 
 WriteString( “Run time is “ );
 WriteLong( newTime - oldTime, 6 );
 WriteString( “ -- press space to exit “ );
 Read( ch );
END DrawDragon.
Listing 3 - Tuned Pen module
(******************************************************)
(* file:  Pen.m    *)
(* Pen methods - see definition module for                 *)
(* descriptions.   *)
(* This version contains improvements suggested by   *)
(* running MPW performance analysis tools.                 *)
(* Written in SemperSoft Modula-2 v.1.1.2                  *)
(* Allen Stenger August 1989    *)
(******************************************************)

IMPLEMENTATION MODULE Pen;

FROM Terminal  IMPORT ClearScreen;
FROM InOutIMPORT Write;
FROM InsideMac   IMPORT FillRect, SetRect;
FROM InsideMac   IMPORT black, Rect;

VAR
 currentDegrees  : [0..359];
 (* direction we are
 facing -- 0 = right. *)
 currentH,
 currentV : CARDINAL;(* where situated *)
 
PROCEDURE Go( distance : CARDINAL );
CONST
 LineSize = 4;
VAR
 lineRect : Rect;
BEGIN
 CASE currentDegrees OF
 0:SetRect( lineRect, currentH, currentV, 
 currentH + distance + LineSize,
 currentV + LineSize ); 
 INC( currentH, distance ); |
 90:    SetRect( lineRect, currentH, currentV, 
 currentH + LineSize,
 currentV + distance + LineSize
 ); 
 INC( currentV, distance ); |
 180: SetRect( lineRect, currentH - distance,
 currentV, 
 currentH + LineSize,
 currentV + LineSize ); 
 DEC( currentH, distance ); |
 270: SetRect( lineRect, currentH, 
 currentV - distance, 
 currentH + LineSize,
 currentV + LineSize ); 
 DEC( currentV, distance ); 
 END; (* CASE *)
 FillRect( lineRect, black );
END Go;

PROCEDURE Turn( degrees : INTEGER );
VAR
 tempDegrees:  INTEGER; 
BEGIN
 tempDegrees := INTEGER(currentDegrees) + degrees;
 DEC( tempDegrees, 360 * ( tempDegrees DIV 360 ) );
 IF tempDegrees < 0 
 THEN INC( tempDegrees, 360 );
 END; (* IF *)
 currentDegrees := tempDegrees;
END Turn;

PROCEDURE Home;
BEGIN
 currentH := 110;
 currentV := 200;
 currentDegrees := 270; (* facing up *)
END Home;

BEGIN
 ClearScreen;
 Write( 0C );  (* graphics initialization kludge *)
END Pen.

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

Bookends 12.8 - Reference management and...
Bookends is a full-featured bibliography/reference and information-management system for students and professionals. Bookends uses the cloud to sync reference libraries on all the Macs you use.... Read more
Apple iTunes 12.6 - Play Apple Music and...
Apple iTunes lets you organize and stream Apple Music, download and watch video and listen to Podcasts. It can automatically download new music, app, and book purchases across all your devices and... Read more
Default Folder X 5.1.4 - Enhances Open a...
Default Folder X attaches a toolbar to the right side of the Open and Save dialogs in any OS X-native application. The toolbar gives you fast access to various folders and commands. You just click on... Read more
Amazon Chime 4.1.5587 - Amazon-based com...
Amazon Chime is a communications service that transforms online meetings with a secure, easy-to-use application that you can trust. Amazon Chime works seamlessly across your devices so that you can... Read more
CrossOver 16.2 - Run Windows apps on you...
CrossOver can get your Windows productivity applications and PC games up and running on your Mac quickly and easily. CrossOver runs the Windows software that you need on Mac at home, in the office,... Read more
Adobe Creative Cloud 4.0.0.185 - Access...
Adobe Creative Cloud costs $19.99/month for a single app, or $49.99/month for the entire suite. Introducing Adobe Creative Cloud desktop applications, including Adobe Photoshop CC and Illustrator CC... Read more
MegaSeg 6.0.2 - Professional DJ and radi...
MegaSeg is a complete solution for pro audio/video DJ mixing, radio automation, and music scheduling with rock-solid performance and an easy-to-use design. Mix with visual waveforms and Magic... Read more
Bookends 12.8 - Reference management and...
Bookends is a full-featured bibliography/reference and information-management system for students and professionals. Bookends uses the cloud to sync reference libraries on all the Macs you use.... Read more
Adobe Creative Cloud 4.0.0.185 - Access...
Adobe Creative Cloud costs $19.99/month for a single app, or $49.99/month for the entire suite. Introducing Adobe Creative Cloud desktop applications, including Adobe Photoshop CC and Illustrator CC... Read more
Default Folder X 5.1.4 - Enhances Open a...
Default Folder X attaches a toolbar to the right side of the Open and Save dialogs in any OS X-native application. The toolbar gives you fast access to various folders and commands. You just click on... Read more

The best deals on the App Store this wee...
Deals, deals, deals. We're all about a good bargain here on 148Apps, and luckily this was another fine week in App Store discounts. There's a big board game sale happening right now, and a few fine indies are still discounted through the weekend.... | Read more »
The best new games we played this week
It's been quite the week, but now that all of that business is out of the way, it's time to hunker down with some of the excellent games that were released over the past few days. There's a fair few to help you relax in your down time or if you're... | Read more »
Orphan Black: The Game (Games)
Orphan Black: The Game 1.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0 (iTunes) Description: Dive into a dark and twisted puzzle-adventure that retells the pivotal events of Orphan Black. | Read more »
The Elder Scrolls: Legends is now availa...
| Read more »
Ticket to Earth beginner's guide: H...
Robot Circus launched Ticket to Earth as part of the App Store's indie games event last week. If you're not quite digging the space operatics Mass Effect: Andromeda is serving up, you'll be pleased to know that there's a surprising alternative on... | Read more »
Leap to victory in Nexx Studios new plat...
You’re always a hop, skip, and a jump away from a fiery death in Temple Jump, a new platformer-cum-endless runner from Nexx Studio. It’s out now on both iOS and Android if you’re an adventurer seeking treasure in a crumbling, pixel-laden temple. | Read more »
Failbetter Games details changes coming...
Sunless Sea, Failbetter Games' dark and gloomy sea explorer, sets sail for the iPad tomorrow. Ahead of the game's launch, Failbetter took to Twitter to discuss what will be different in the mobile version of the game. Many of the changes make... | Read more »
Splish, splash! The Pokémon GO Water Fes...
Niantic is back with a new festival for dedicated Pokémon GO collectors. The Water Festival officially kicks off today at 1 P.M. PDT and runs through March 29. Magikarp, Squirtle, Totodile, and their assorted evolved forms will be appearing at... | Read more »
Death Road to Canada (Games)
Death Road to Canada 1.0 Device: iOS Universal Category: Games Price: $7.99, Version: 1.0 (iTunes) Description: Get it now at the low launch price! Price will go up a dollar every major update. Update news at the bottom of this... | Read more »
Bean's Quest Beginner's Guide:...
Bean's Quest is a new take on both the classic platformer and the endless runner, and it's free on the App Store for the time being. Instead of running constantly, you can't stop jumping. That adds a surprising new level of challenge to the game... | Read more »

Price Scanner via MacPrices.net

2.6GHz Mac mini on sale for $559, $140 off MS...
Guitar Center has the 2.6GHz Mac mini (MGEN2LL/A) on sale for $559 including free shipping. Their price is $140 off MSRP, and it’s the lowest price available for this model. Read more
SSD Speeder RAM Disk SSD Life Extender App Fo...
Fehraltorf, Switzerland based B-Eng has announced they are making their SSD Speeder app for macOS publicly available for purchase on their website. SSD Speeder is a RAM disk utility that prevents... Read more
iPhone Scores Highest Overall in Smartphone D...
Customer satisfaction is much higher among smartphone owners who use their device to operate other connected home services such as smart thermostats and smart appliances, according to the J.D. Power... Read more
Swipe CRM Free Photo-Centric CRM Sales DEal C...
Swipe CRM LLC has introduced Swipe CRM: Visual Sales 1.0 for iPad, an app for creating, managing, and sharing visually stunning sales deals. Swipe CRM is targeted to small-and-medium creative... Read more
13-inch 2.0GHz Apple MacBook Pros on sale for...
B&H has the non-Touch Bar 13″ 2.0GHz MacBook Pros in stock today and on sale for $150 off MSRP. Shipping is free, and B&H charges NY sales tax only: - 13″ 2.0GHz MacBook Pro Space Gray (... Read more
15-inch Touch Bar MacBook Pros on sale for up...
B&H Photo has the new 2016 15″ Apple Touch Bar MacBook Pros in stock today and on sale for up to $150 off MSRP. Shipping is free, and B&H charges NY sales tax only: - 15″ 2.7GHz Touch Bar... Read more
Apple’s iPhone 6s Tops Best-Selling Smartphon...
In terms of shipments, the iPhone 6s from Apple bested all competitors for sales in 2016, according to new analysis from IHS Markit, a world leader in critical information, analytics and solutions.... Read more
Logitech Rugged Combo Protective iPad Case an...
Logitech has announced its Logitech Rugged Combo, Logitech Rugged Case, and Logitech Add-on Keyboard for Rugged Case for Apple’s new, more affordable $329 9.7-inch iPad, a complete solution designed... Read more
T-Mobile To Offer iPhone 7 and iPhone 7 Plus...
T-Mobile has announced it will offer iPhone 7 and iPhone 7 Plus (PRODUCT)RED Special Edition in a vibrant red aluminum finish. The introduction of this special edition iPhone celebrates Apple’s 10... Read more
9-inch 128GB iPad Pros on sale for $50-$70 of...
B&H Photo has 9.7″ 128GB Apple WiFi iPad Pros on sale for up to $70 off MSRP, each including free shipping. B&H charges sales tax in NY only: - 9″ Space Gray 128GB WiFi iPad Pro: $649 $50... Read more

Jobs Board

*Apple* Retail - Multiple Positions - Apple,...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
Fulltime aan de slag als shopmanager in een h...
Ben jij helemaal gek van Apple -producten en vind je het helemaal super om fulltime shopmanager te zijn in een jonge en hippe elektronicazaak? Wil jij werken in Read more
Starte Dein Karriere-Abenteuer in den Hauptst...
…mehrsprachigen Teams betreust Du Kunden von bekannten globale Marken wie Apple , Mercedes, Facebook, Expedia, und vielen anderen! Funktion Du wolltest schon Read more
*Apple* Retail - Multiple Positions- Chicago...
SalesSpecialist - Retail Customer Service and SalesTransform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
Fulltime aan de slag als shopmanager in een h...
Ben jij helemaal gek van Apple -producten en vind je het helemaal super om fulltime shopmanager te zijn in een jonge en hippe elektronicazaak? Wil jij werken in Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.