TweetFollow Us on Twitter

High Res Timer
Volume Number:8
Issue Number:1
Column Tag:c workshop

Related Info: Time Manager

A High-Resolution Timer

A simple package for measuring small intervals of time for performance analysis

By Martin Minow, Arlington, Massachusetts

Note: Source code files accompanying article are located on MacTech CD-ROM or source code disks.

Introduction

Volume 6 of Inside Macintosh - which is to say late System 6.0 and System 7 - describes the extended TimeManager and a drift-free timer function that lets an application measure durations with a finer resolution than the 1/60 second system tick count.

In order to simplify measuring small intervals for performance analysis, I wrote a simple package that allows recording the “time of day” at its highest resolution. Using this as a base, you can record the start and end of an event of interest (such as a subroutine call) and, by using one of the subroutines in the package, determine the elapsed time.

For my particular purposes, elapsed times are recorded in integers with microsecond resolution, giving a maximum interval of just over 35 minutes, since 231 is greater than (35 * 60 * 1000000). If you need to record longer intervals, you need only redo the DeltaTime subroutine (as shown in the demo application) so it returns a floating-point (double-precision) value.

The demo program shows some of the calls and lets you get an idea of the amount of time needed to setup and call the timer service. On my Macintosh IIci with the THINK C debugger enabled, the average time is about 160µsec, which is not shabby at all. Of course, you should not assume that microsecond resolution means microsecond accuracy.

InitializeMicrosecondTimer will return an error if the drift-free timer is not supported on your system. Because of the way it calls Gestalt, you must compile it on a modern system (THINK C 5.0) as the “glue” that calls Gestalt now includes code to check for the Gestalt trap presence.

In order to ensure that the timer routine’s periodic task is removed when your application exits, InitializeMicrosecondTimer patches the ExitToShell trap for the removal function. Because of the way THINK C installs its own ExitToShell trap, be sure to call InitializeMicrosecondTimer before calling any THINK C routines from the standard I/O or THINK Class libraries.

Acknowledgments

This is a revision of a program I first wrote for the IBM 7090 in 1964. OK, maybe it was 1965. Some of the Macintosh specific code can be traced to a timing routine in the MacDTS “FracApp” demonstration program by Keith Rollin and Bo3b Johnson, while the exit handler is based on code in the atexit function in the THINK C library.

Listing:  MicrosecondTimer.h

/* MicrosecondTimer.h*/
/*
 * Time measurement.
 * Copyright © 1991 Martin Minow.  All Rights Reserved
 *
/*
 * Definitions for the Millisecond timer
 */
#ifndef _H_MsecTimer
#define _H_MsecTimer

#define MSEC_PER_TICK1

typedef struct MicrosecondEpoch {
 unsigned long time; /* Time of day*/
 signed longmicrosecond;  /* Residual*/
} MicrosecondEpoch, *MicrosecondEpochPtr;

/*
 * Initialize the clock - call once when your
 * application starts.
 */
OSErr   InitializeMicrosecondTimer(void);
/*
 * Cancel the clock - this is called automatically
 * when your application exits.
 */
void    CancelMicrosecondTimer(void);
/*
 * Return the current extended time value.
 */
void    GetEpoch(MicrosecondEpochPtr result);
/*
 * Compute the difference between two epoch’s. The
 * result is in deltaTime (in microseconds).
 * deltaTime is positive if epoch2 is later than epoch1.
 *
 * Returns TRUE if the time can be represented in
 * microseconds (less than 35 minutes difference). 
 * If it returns FALSE, deltaTime is likely to be garbage.
 */
Boolean DeltaTime(
 MicrosecondEpochPtr epoch1,
 MicrosecondEpochPtr epoch2,
 signed long*deltaTime
 );
/*
 * Compute the difference between two epoch’s. The
 * result is returned as a floating-point number
 * of seconds.
 */
double  DoubleDelta(
 MicrosecondEpoch*start,
 MicrosecondEpoch*finish
 );

/*
 * Format an epoch value as “hh:mm:ss.fraction”
 */
void EpochToString(
 MicrosecondEpochPtr epochPtr,
 StringPtrresult
 );
/*
 * Use an extended time value to adjust the
 * local clock.  Unfortunately, we can only adjust
 * the clock by an integral number of seconds.
 */
void AdjustClock(
 signed longadjustment
 );
#endif
Listing:  MicrosecondTimer.c

/* MicrosecondTimer.c*/
/*
 * Time measurement.
 * Copyright © 1991 Martin Minow.  All Rights Reserved
 *
 * This function creates a high-resolution “time of day”
 * timer that is (or, at least, ought to be) synchronized
 * with the system time of day value.  It uses the
 * new time manager calls.
 *
 * In order to keep our timer in reasonable synchronization
 * with the system time of day, we shadow that value at
 * each time-of-day trap.
 * 
 * Usage:
 * InitializeMicrosecondTimer(void);
 * Call this - once - when your program starts. It
 * installs the timer interrupt routine. It returns
 * noErr if successful, or unimpErr if the Extended
 * Time Manager is not supported on this system.
 *
 * Important: if you are using the THINK C ANSI,
 * console, or class libraries, be sure to call
 * InitializeMicrosecondTimer before calling any
 * THINK C routines.  Otherwise, your program
 * may crash on exit under certain ill-defined
 * circumstances.
 *
 * CancelMicrosecondTimer(void)
 * This must be called before your application exits.
 * InitializeMSecTimer() establishes an exit handeler
 * to force its call, so you needn’t worry about it.
 *
 * GetEpoch(
 * MicrosecondEpoch *result
 * )
 * Call this to get the time of day. The result
 * consists of a time (seconds) value that is
 * intended to track GetTimeOfDay exactly, extended
 * by the number of microseconds past this second.
 *
 * DeltaTime(
 * MicrosecondEpoch*startTime,
 * MicrosecondEpoch*endTime
 * signed long   *difference
 * )
 * Compute the difference between two extended
 * time values, returning the result in the third
 * parameter (as a signed number of microseconds).
 * The result will be positive if time2 is later
 * than time1. DeltaTime returns TRUE if the
 * absolute value of the difference (in seconds)
 * is less than 35 minutes (a signed longword can
 * resolve a 34 minute interval). (You might want
 * to redo this to return a double-precision format
 * value, rather than a longword.)
 *
 * DoubleDelta(
 * MicrosecondEpoch*start,
 * MicrosecondEpoch*finish
 * )
 * Compute the difference between two extended
 * time values, returning the result as a double-
 * precision number of seconds.
 * 
 * EpochToString(
 * MicrosecondEpoch*epoch
 * Str255 result
 * )
 * Convert an extended time value to a fixed-width,
 * fixed-format Pascal string “hh:mm:ss.fraction”.
 *
 * Although the code has not been tested under MPW, it
 * ought to port easily: just re-do the asm stuff.
 *
 * Acknowledgements:
 * Parts of the time manager calls are based on a
 * timing module in the MacDTS FracApp demo program
 * by Keith Rollin an Bo3b Johnson.
 *
 * The exit handler is based on similar code in the
 * atexit() function in the THINK C support library.
 */

#include <GestaltEqu.h>
#ifndef THINK_C
#include <SysEqu.h>
#endif
#include <Timer.h>
#include <Traps.h>
#include “MicrosecondTimer.h”

/*
 * This is needed to establish an exit trap handler.
 */
typedef void(*MyProcPtr)(void);
typedef struct {
 short  jmp;
 MyProcPtrfunction;
} JumpVector;

static void *oldExitVector;
static JumpVector*jumpVector;
static void TimerExitHandler(void);

#define MILLION  (1000000L)

/*
 * This is a time manager record, extended to include a
 * shadow copy of the system time of day value that is
 * updated once a second.
 */
typedef struct TimeInfoRecord {
 TMTask TMTask;  /* The task record*/
 unsigned long epoch;/* Time of day info     */
} TimeInfoRecord, *TimeInfoPtr;

static TimeInfoRecordgTimeInfo;
#define TIME(gTimeInfo.TMTask)
static long gOverheadTime;
static pascal void TimeCounter(void);

static void Concat(StringPtr dst, StringPtr src);

/*
 * Install a timer interrupt procedure.
 */
OSErr
InitializeMicrosecondTimer()
{
 long   timeOfDay;
 long   gestaltResult;
 OSErr  status;
 
 if (TIME.tmAddr != NULL)
 status = noErr; /* Already installed*/
 else {
 status = Gestalt(
 gestaltTimeMgrVersion,
 &gestaltResult
 );
 if (status == noErr
  && gestaltResult < gestaltExtendedTimeMgr)
 status = unimpErr;
 if (status == noErr) {
 /*
  * Install a trap handler for ExitToShell
  */
 oldExitVector =
 (void *) GetTrapAddress(_ExitToShell);
 if (ROM85 >= 0) {
 SetTrapAddress(
 (long) TimerExitHandler,
 _ExitToShell
 );
 }
 else {
 /*
  * Install a trap handler
  * in the system heap.
  */
 jumpVector = (JumpVector *)
 NewPtrSys(sizeof (JumpVector));
 if (jumpVector == NULL) {
 status = memFullErr;
 goto exit;
 }
 else {
 jumpVector->jmp = 0x4EF9;
 jumpVector->function =
 TimerExitHandler;
 SetTrapAddress(
 (long) jumpVector,
 _ExitToShell
 );
 }

 }
 /*
  * Install the time manager task and
  * start it rolling.
  */
 TIME.tmAddr = (ProcPtr) TimeCounter;
 InsXTime(&TIME);
 /*
  * Align our timer to the system’s
  */
 timeOfDay = Time;
 do {
 gTimeInfo.epoch = Time;
 } while (timeOfDay == gTimeInfo.epoch);
 /*
  * We should really do this a bunch
  * of times and take the minimum.
  * gOverheadTime measures the amount
  * of time the PrimeTime/RmvTime sequence
  * requires, See the discussion in IM-VI.
  */
 PrimeTime(&TIME, -MILLION);
 RmvTime(&TIME);
 gOverheadTime = MILLION + TIME.tmCount;
 /*
  * Restart the timer
  */
 InsXTime(&TIME);
 PrimeTime(&TIME, 0);
 }
 }
exit: return (status);
}

/*
 * GetEpoch returns the current extended time of day.
 * It requires the drift-free time manager. See the
 * Time Manager discussion in Inside Mac VI for details
 * of the procedure.
 */
void
GetEpoch(
 MicrosecondEpochPtr result
 )
{
 RmvTime(&TIME); /* Stop Clock*/
 result->time = gTimeInfo.epoch; /* Get seconds    */
 /*
  * TIME.tmCount contains the residual number of
  * microseconds. This is a negative number (see
  * IM-VI). The following, then, computes the
  * number of microseconds that have elapsed in
  * the current second.
  */
 result->microsecond = 
 (MILLION + TIME.tmCount) /* Offset “now”    */
 - gOverheadTime;/* - call cost  */
 if (result->microsecond < 0) {  /* New second?    */
 result->time -= 1;/* Correct it.  */
 result->microsecond += MILLION;
 }
 InsXTime(&TIME);/* Drift-free*/
 PrimeTime(&TIME, 0);/* Timer start*/
}

/*
 * Return the difference between two (nearby) epochs.
 * The result is in microseconds and has a range of
 * up to about 35 minutes.
 *
 * DeltaTime returns TRUE if deltaTime is valid.
 */
Boolean
DeltaTime(
 MicrosecondEpochPtr epoch1,
 MicrosecondEpochPtr epoch2,
 signed long*deltaTime
 )
{
 long   seconds;
 long   microseconds;
 
 seconds = epoch2->time - epoch1->time;
 microseconds =
 epoch2->microsecond - epoch1->microsecond;
 *deltaTime = (seconds * MILLION) + microseconds;
 /*
  * The result is valid only if the
  * absolute value of the difference is
  * less than about 35 minutes.  I.e.
  *2^31 <= (35 * 60 * 10^6)
  */
 if (seconds < 0)
 seconds = (-seconds);
 return (seconds <= (34 * 60));
}

/*
 * Return the time difference as a double-precision
 * number of seconds.
 */
double
DoubleDelta(
 MicrosecondEpoch*start,
 MicrosecondEpoch*finish
 )
{
 double seconds;
 double microseconds;
 double result;
 
 seconds = finish->time - start->time;
 microseconds =
 finish->microsecond - start->microsecond;
 result = seconds
    + (microseconds / (double) MILLION);
 return (result);
}


/*
 * This local function formats hour:minute:second.
 */
static void
FormatTimeString(
 StringPtrresult,
 long   what,
 BooleanneedColon
 )
{
 Str255 value;
 
 if (needColon)
 result[++result[0]] = ‘:’;
 NumToString(what, value);
 if (value[0] == 1)
 result[++result[0]] = ‘0’;
 Concat(result, value);
}

/*
 * Convert the time of day to a consistent, fixed-width
 * format of hh:mm:ss.microseconds. This is always in
 * 24 hour format.
 */
void
EpochToString(
 MicrosecondEpochPtr epochPtr,
 StringPtrresult
 )
{
 unsigned int    i;
 DateTimeRecnow;
 Str255 value;

 Secs2Date(epochPtr->time, &now);
 result[0] = 0;
 FormatTimeString(result, now.hour,   FALSE);
 FormatTimeString(result, now.minute, TRUE);
 FormatTimeString(result, now.second, TRUE);
 NumToString(
 epochPtr->microsecond + MILLION,
 value
 );
 value[1] = ‘.’;
 Concat(result, value);
}

/*
 * String concatenator for Pascal strings.
 */
static void
Concat(
 StringPtrdst,
 StringPtrsrc
 )
{
 short  copySize;
 
 copySize = src[0];
 if ((copySize + dst[0]) > 255)
 copySize = 255 - dst[0];
 BlockMove(
 &src[1],
 &dst[dst[0] + 1],
 (long) copySize
 );
 dst[0] += copySize;
}

/*
 * Adjust the clock by adding the adjustment to the
 * current clock.  There is a built-in delay to
 * make sure our timer task gets to do its thing.
 *
 * Note: the right way to do this is to change the system
 * clock tick base from 1000000 and continually adjust
 * the clock a bit every second until it’s right.
 * Unfortunately, we don’t have access to the system
 * clock time manager record.
 */
void
AdjustClock(
 long   adjustment
 )
{
 MicrosecondEpochourEpoch;
 long   timeOfDay;

 GetEpoch(&ourEpoch);
 ourEpoch.time += (adjustment / MILLION);
 adjustment %= MILLION;
 if (ourEpoch.microsecond >= (MILLION / 2))
 ourEpoch.time += 1;
 else if (ourEpoch.microsecond <= (-(MILLION / 2)))
 ourEpoch.time -= 1;
 SetDateTime(ourEpoch.time);
 /*
  * Vamp until our shadow clock has a chance to
  * update the local value.
  */
 GetEpoch(&ourEpoch);
 timeOfDay = ourEpoch.time;
 do {
 GetEpoch(&ourEpoch);
 } while (timeOfDay == ourEpoch.time);
}

/*
 * This will be called automatically by the
 * ExitToShell trap.
 */
void
CancelMicrosecondTimer()
{

#if 0 /* Enable this to put a debug trap here                  */
 asm {
 nop
 }
#endif
 if (TIME.tmAddr != NULL) {
 RmvTime(&TIME);
 TIME.tmAddr = NULL;
 }
 if (oldExitVector != NULL) {
 SetTrapAddress(
 (long) oldExitVector,
 _ExitToShell
 );
 oldExitVector = NULL;
 if (jumpVector != NULL) {
 DisposPtr(jumpVector);
 jumpVector = NULL;
 }
 }
}

/*
 * This is called by the ExitToShell trap.
 * It cancels the timer service and removes
 * itself from the trap process, then re-calls
 * ExitToShell to allow other trap handlers to
 * execute.
 */
static void
TimerExitHandler()
{
 long   oldA5 = SetCurrentA5();

 CancelMicrosecondTimer();
 SetA5(oldA5);
 ExitToShell();  /* Call next exit handler   */
}

/*
 * This private routine is called by the TimeManager at
 * every clock tick. There is blood on every line of this
 * function - and on a number of lines of code that aren’t
 * here any more. This function will need to be rewritten
 * for MPW-C, as that compiler lacks an asm statement.
 */
static pascal void
TimeCounter()
{
 asm {
 /*
  * When we are called, A1 -> the time info
  * record which we have extended with our
  * “time of day” shadow. Update it with the
  * current system time-of-day value (so that
  * we remain coordinated with any changes
  * caused by SetDateTime or Control Panel
  * calls). This may mean that we are up to
  * one second out of step from the system, but
  * this probably can’t be helped.  TimeLM is
  * the system global “time of day” variable.
  * This variable has a different name in MPW-C.
  */
 move.l TimeLM,  \
 OFFSET(TimeInfoRecord,epoch)(a1)
 move.l a1,a0    ;; a0 = TmTaskPtr 
 move.l #-MILLION,d0 ;; d0 = count
 dc.w 0xA05A;; _PrimeTime
 }
}
Listing:  MicrosecondTimerDemo.c

/* MicrosecondTimerDemo.c */
/*
 * This is a totally useless demo program that scribbles
 * the time of day as quickly as it can, then it tries
 * to determine the cost of calling the time routines.
 * Click on the mouse whenever you get bored.
 */
#include <stdio.h>
#include <console.h>
#include <limits.h>
#include <math.h>
#include “MicrosecondTimer.h”
#define MILLION  (1000000L)
#define HIST_MAX 100
#define HIST_SIZE(100L) /* 100 microseconds per bin      */
double  histogram[HIST_MAX];
double  overflow;

main(
 int    argc,
 char   **argv
 )
{
 MicrosecondEpochthen;
 MicrosecondEpochnow;
 MicrosecondEpochstart;
 MicrosecondEpochfinish;
 long   elapsed;
 long   smallest;
 long   biggest;
 double trials;
 double sum, sumSq;
 double mean, variance, sd;
 double seconds;
 double trialTime;
 register short  i,top;
 Str255 message;

 /*
  * Be sure to initialize the timer before calling
  * any THINK C stdio or THINK Class Library
  * routines.
  */
 InitializeMicrosecondTimer();
 argc = ccommand(&argv);
 printf(“Hit the mouse to stop\n”);
 GetEpoch(&then);
 while (Button() == FALSE) {
 SystemTask();
 GetEpoch(&now);
 EpochToString(&now, message);
 DeltaTime(&then, &now, &elapsed);
 printf(
 “%#s - %ld.%06ld\n”,
 message,
 elapsed / MILLION,
 elapsed % MILLION
 );
 then = now;
 }
 while (Button())
 ;
 printf(“Beginning timer resolution test.\n”);
 printf(“Hit the mouse to stop\n”);
 smallest = LONG_MAX;
 biggest = 0;
 trials = 0;
 sum = sumSq = 0;
 i = 0;
 GetEpoch(&start);
 while (Button() == FALSE) {
 if ((++i % 1000) == 0)
 SystemTask();
 GetEpoch(&then);
 GetEpoch(&now);
 DeltaTime(&then, &now, &elapsed);
 if (elapsed < smallest)
 smallest = elapsed;
 if (elapsed > biggest)
 biggest = elapsed;
 sum += elapsed;
 sumSq += (elapsed * elapsed);
 trials++;
 i = elapsed / HIST_SIZE;
 if (i >= HIST_MAX)
 ++overflow;
 else {
 ++histogram[i];
 }
 }
 while (Button())
 ;
 GetEpoch(&finish);
 top = HIST_MAX;
 if (overflow == 0) {
 while (top > 0 && histogram[top - 1] == 0)
 top -= 1;
 }
 printf(“Each histogram bucket contains %ld µsec.\n”,
 HIST_SIZE);
 for (i = 0; i < top; i++) {
 printf(“%5ld: %.0f\n”,
 i * HIST_SIZE, histogram[i]);
 }
 if (overflow > 0)
 printf(“%.0f overflow\n”);
 printf(“Timer minimum = %ld.%06ld,”,
 smallest / MILLION,
 smallest % MILLION
 );
 printf(“ maximum = %ld.%06ld\n”,
 biggest / MILLION,
 biggest % MILLION
 );
 printf(“%.0f trials”, trials);
 if (trials > 0) {
 mean = sum / trials;
 printf(“: mean %.2f µsec.”, mean);
 if (trials > 1.0)  {
 /*
  * No, this is not the proper way to
  * calculate the variance.
  */
 variance = (sumSq * trials) - (sum * sum);
 variance /= (trials * trials);
 sd = sqrt(variance);/* Std. deviation */
 printf(“, variance %0.2f,”, variance);
 printf(“ standard deviation %0.2f”, sd);
 }
 }
 printf(“\n”);
 seconds = DoubleDelta(&start, &finish);
 printf(“%0.3f seconds”, seconds);
 if (seconds > 0.0)
 printf(“, %0.2f trials/sec.”, trials / seconds);
 if (trials > 0.0) {
 trialTime = (seconds * (double) MILLION) / trials;
 printf(“, %.2f µsec./trial\n”, trialTime);
 printf(“%.2f µsec. mean test overhead”,
 trialTime - mean
 );
 }
 printf(“\n”);
}







  
 
AAPL
$116.47
Apple Inc.
+0.16
MSFT
$47.98
Microsoft Corpora
-0.72
GOOG
$537.50
Google Inc.
+2.67

MacTech Search:
Community Search:

Software Updates via MacUpdate

Cobook 3.0.7 - Intelligent address book....
Cobook Contacts is an intuitive, engaging address book. Solve the problem of contact management with Cobook Contacts and its simple interface and powerful syncing and integration possibilities.... Read more
StatsBar 1.9 - Monitor system processes...
StatsBar gives you a comprehensive and detailed analysis of the following areas of your Mac: CPU usage Memory usage Disk usage Network and bandwidth usage Battery power and health (MacBooks only)... Read more
Cyberduck 4.6 - FTP and SFTP browser. (F...
Cyberduck is a robust FTP/FTP-TLS/SFTP browser for the Mac whose lack of visual clutter and cleverly intuitive features make it easy to use. Support for external editors and system technologies such... Read more
Maya 2015 - Professional 3D modeling and...
Maya is an award-winning software and powerful, integrated 3D modeling, animation, visual effects, and rendering solution. Because Maya is based on an open architecture, all your work can be scripted... Read more
Evernote 6.0.1 - Create searchable notes...
Evernote allows you to easily capture information in any environment using whatever device or platform you find most convenient, and makes this information accessible and searchable at anytime, from... Read more
calibre 2.11 - Complete e-library manage...
Calibre is a complete e-book library manager. Organize your collection, convert your books to multiple formats, and sync with all of your devices. Let Calibre be your multi-tasking digital... Read more
Herald 5.0.1 - Notification plugin for M...
Note: Versions 2.1.3 (for OS X 10.7), 3.0.6 (for OS X 10.8), and 4.0.8 (for OS X 10.9) are no longer supported by the developer. Herald is a notification plugin for Mail.app, Apple's Mac OS X email... Read more
Firetask 3.7 - Innovative task managemen...
Firetask uniquely combines the advantages of classical priority-and-due-date-based task management with GTD. Stay focused and on top of your commitments - Firetask's "Today" view shows all relevant... Read more
TechTool Pro 7.0.6 - Hard drive and syst...
TechTool Pro is now 7, and this is the most advanced version of the acclaimed Macintosh troubleshooting utility created in its 20-year history. Micromat has redeveloped TechTool Pro 7 to be fully 64... Read more
PhotoDesk 3.0.1 - Instagram client for p...
PhotoDesk lets you view, like, comment, and download Instagram pictures/videos! (NO Uploads! / Image Posting! Instagram forbids that! AND you *need* an *existing* Instagram account). But you can do... Read more

Latest Forum Discussions

See All

Ubisoft Gives Everyone Two New Ways to E...
Ubisoft Gives Everyone Two New Ways to Earn In-Game Stuff for Far Cry 4 Posted by Jessica Fisher on November 21st, 2014 [ permalink ] | Read more »
Golfinity – Tips, Tricks, Strategies, an...
Dig this: Would you like to know what we thought of being an infinite golfer? Check out our Golfinity review! Golfinity offers unlimited ways to test your skills at golf. Here are a few ways to make sure your score doesn’t get too high and your... | Read more »
Dark Hearts, The Sequel to Haunting Meli...
Dark Hearts, The Sequel to Haunting Melissa, is Available Now Posted by Jessica Fisher on November 21st, 2014 [ permalink ] Universal App - Designed for iPhone and iPad | Read more »
Meowza! Toyze Brings Talking Tom to Life...
Meowza! | Read more »
Square Enix Announces New Tactical RPG f...
Square Enix Announces New Tactical RPG for Mobile, Heavenstrike Rivals. Posted by Jessica Fisher on November 21st, 2014 [ permalink ] With their epic stories and gorgeous graphics, | Read more »
Quest for Revenge (Games)
Quest for Revenge 1.0.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.0 (iTunes) Description: The great Kingdom of the west has fallen. The gods ignore the prayers of the desperate. A dark warlord has extinguished... | Read more »
Threadz is a New Writing Adventure for Y...
Threadz is a New Writing Adventure for You and Your Friends Posted by Jessica Fisher on November 21st, 2014 [ permalink ] In the tradition of round-robin storytelling, | Read more »
SteelSeries Stratus XL Hardware Review
Made by: SteelSeries Price: $59.99 Hardware/iOS Integration Rating: 4 out of 5 stars Usability Rating: 4.5 out of 5 stars Reuse Value Rating: 4.25 out of 5 stars Build Quality Rating: 4.5 out of 5 stars Overall Rating: 4.31 out of 5 stars | Read more »
ACDSee (Photography)
ACDSee 1.0.0 Device: iOS iPhone Category: Photography Price: $1.99, Version: 1.0.0 (iTunes) Description: Capture, perfect, and share your photos with ACDSee. The ACDSee iPhone app combines an innovative camera, a powerful photo... | Read more »
ProTube for YouTube (Entertainment)
ProTube for YouTube 2.0.2 Device: iOS Universal Category: Entertainment Price: $1.99, Version: 2.0.2 (iTunes) Description: ProTube is the ultimate, fully featured YouTube app. With it's highly polished design, ProTube offers ad-free... | Read more »

Price Scanner via MacPrices.net

Save up to $400 with Apple refurbished 2014 1...
The Apple Store has restocked Apple Certified Refurbished 2014 15″ Retina MacBook Pros for up to $400 off the cost of new models. An Apple one-year warranty is included with each model, and shipping... Read more
New 13-inch 1.4GHz MacBook Air on sale for $8...
 Adorama has the 2014 13″ 1.4GHz/128GB MacBook Air on sale for $899.99 including free shipping plus NY & NJ tax only. Their price is $100 off MSRP. B&H Photo has the 13″ 1.4GHz/128GB MacBook... Read more
Apple Expected to Reverse Nine-Month Tablet S...
Apple and Samsung combined accounted for 62 percent of the nearly 36 million branded tablets shipped in 3Q 2014, according to early vendor shipment share estimates from market intelligence firm ABI... Read more
Stratos: 30 Percent of US Smartphone Owners t...
Stratos, Inc., creator of the Bluetooth Connected Card Platform, has announced results from its 2014 Holiday Mobile Payments Survey. The consumer survey found that nearly one out of three (30 percent... Read more
2014 1.4GHz Mac mini on sale for $449, save $...
 B&H Photo has lowered their price on the new 1.4GHz Mac mini to $449.99 including free shipping plus NY tax only. Their price is $50 off MSRP, and it’s the lowest price available for this new... Read more
Check Apple prices on any device with the iTr...
MacPrices is proud to offer readers a free iOS app (iPhones, iPads, & iPod touch) and Android app (Google Play and Amazon App Store) called iTracx, which allows you to glance at today’s lowest... Read more
64GB iPod touch on sale for $249, save $50
Best Buy has the 64GB iPod touch on sale for $249 on their online store for a limited time. Their price is $50 off MSRP. Choose free shipping or free local store pickup (if available). Sale price for... Read more
15″ 2.2GHz Retina MacBook Pro on sale for $17...
 B&H Photo has the 2014 15″ 2.2GHz Retina MacBook Pro on sale for $1799.99 for a limited time. Shipping is free, and B&H charges NY sales tax only. B&H will also include free copies of... Read more
New Logitech AnyAngle Case/Stand Brings Flexi...
Logitec has announced the newest addition to its suite of tablet products — the Logitech AnyAngle. A protective case with an any-angle stand for iPad Air 2 and all iPad mini models, AnyAngle is the... Read more
Notebook PC Shipments Rise Year-Over-Year as...
According to preliminary results from the upcoming DisplaySearch Quarterly Mobile PC Shipment and Forecast Report, the global notebook PC market grew 10 percent year-over-year in Q3’14 to 49.4... Read more

Jobs Board

*Apple* Solutions Consultant (ASC)- Retail S...
**Job Summary** The ASC is an Apple employee who serves as an Apple brand ambassador and influencer in a Reseller's store. The ASC's role is to grow Apple Read more
Project Manager, *Apple* Financial Services...
**Job Summary** Apple Financial Services (AFS) offers consumers, businesses and educational institutions ways to finance Apple purchases. We work with national and Read more
*Apple* Store Leader Program - College Gradu...
Job Description: Job Summary As an Apple Store Leader Program agent, you can continue your education as you major in the art of leadership at the Apple Store. You'll Read more
*Apple* Retail - Multiple Positions (US) - A...
Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, you're also the Read more
Senior Event Manager, *Apple* Retail Market...
…This senior level position is responsible for leading and imagining the Apple Retail Team's global event strategy. Delivering an overarching brand story; in-store, Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.