1 files changed, 259 insertions, 0 deletions
diff --git a/lib/perf_check.cpp b/lib/perf_check.cpp
new file mode 100644
index 00000000..897be12c
--- /dev/null
+++ b/lib/perf_check.cpp
@@ -0,0 +1,259 @@
+// **************************************************************************
+// * This file is part of the FreeFileSync project. It is distributed under *
+// * GNU General Public License: http://www.gnu.org/licenses/gpl.html       *
+// * Copyright (C) ZenJu (zhnmju123 AT gmx DOT de) - All Rights Reserved    *
+// **************************************************************************
+
+#include "perf_check.h"
+
+#include <limits>
+//#include <wx/ffile.h>
+#include <zen/basic_math.h>
+#include <zen/i18n.h>
+#include <wx+/format_unit.h>
+
+using namespace zen;
+
+
+PerfCheck::PerfCheck(unsigned windowSizeRemainingTime,
+                     unsigned windowSizeBytesPerSecond) :
+    windowSizeRemTime(windowSizeRemainingTime),
+    windowSizeBPS(windowSizeBytesPerSecond),
+    windowMax(std::max(windowSizeRemainingTime, windowSizeBytesPerSecond)) {}
+
+
+PerfCheck::~PerfCheck()
+{
+    /*
+    //write samples to a file
+    wxFFile outputFile(wxT("statistics.dat"), wxT("w"));
+
+    outputFile.Write(wxT("Time(ms);Objects;Data\n"));
+
+    for (auto iter = samples.begin(); iter != samples.end(); ++iter)
+    {
+        outputFile.Write(numberTo<wxString>(iter->first));
+        outputFile.Write(wxT(";"));
+        outputFile.Write(numberTo<wxString>(iter->second.objCount_));
+        outputFile.Write(wxT(";"));
+    	outputFile.Write(numberTo<wxString>(iter->second.data_));
+        outputFile.Write(wxT("\n"));
+    }
+    */
+}
+
+
+void PerfCheck::addSample(int objectsCurrent, double dataCurrent, long timeMs)
+{
+    samples.insert(samples.end(), std::make_pair(timeMs, Record(objectsCurrent, dataCurrent))); //use fact that time is monotonously ascending
+
+    //remove all records earlier than "now - windowMax"
+    const long newBegin = timeMs - windowMax;
+    auto iterWindowBegin = samples.upper_bound(newBegin);
+    if (iterWindowBegin != samples.begin())
+        samples.erase(samples.begin(), --iterWindowBegin); //keep one point before newBegin in order to handle "measurement holes"
+}
+
+
+wxString PerfCheck::getRemainingTime(double dataRemaining) const
+{
+    if (!samples.empty())
+    {
+        const auto& recordBack = *samples.rbegin();
+        //find start of records "window"
+        auto iterFront = samples.upper_bound(recordBack.first - windowSizeRemTime);
+        if (iterFront != samples.begin())
+            --iterFront; //one point before window begin in order to handle "measurement holes"
+
+        const auto& recordFront = *iterFront;
+        //-----------------------------------------------------------------------------------------------
+        const double timeDelta = recordBack.first        - recordFront.first;
+        const double dataDelta = recordBack.second.data_ - recordFront.second.data_;
+
+        //objects do *NOT* correspond to disk accesses, so we better play safe and use "bytes" only!
+        //https://sourceforge.net/tracker/index.php?func=detail&aid=3452469&group_id=234430&atid=1093083
+
+        if (!numeric::isNull(dataDelta)) //sign(dataRemaining) != sign(dataDelta) usually an error, so show it!
+        {
+            int remTimeSec = dataRemaining * timeDelta / (1000.0 * dataDelta);
+            return zen::remainingTimeToShortString(remTimeSec);
+        }
+    }
+    return wxT("-"); //fallback
+}
+
+
+wxString PerfCheck::getBytesPerSecond() const
+{
+    if (!samples.empty())
+    {
+        const auto& recordBack = *samples.rbegin();
+        //find start of records "window"
+        auto iterFront = samples.upper_bound(recordBack.first - windowSizeBPS);
+        if (iterFront != samples.begin())
+            --iterFront; //one point before window begin in order to handle "measurement holes"
+
+        const auto& recordFront = *iterFront;
+        //-----------------------------------------------------------------------------------------------
+        const double timeDelta = recordBack.first        - recordFront.first;
+        const double dataDelta = recordBack.second.data_ - recordFront.second.data_;
+
+        if (!numeric::isNull(timeDelta))
+            if (dataDelta > 0) //may be negative if user cancels copying
+                return zen::filesizeToShortString(zen::Int64(dataDelta * 1000 / timeDelta)) + _("/sec");
+    }
+    return wxT("-"); //fallback
+}
+
+
+wxString PerfCheck::getOverallBytesPerSecond() const //for all samples
+{
+    if (!samples.empty())
+    {
+        const auto& recordBack  = *samples.rbegin();
+        const auto& recordFront = *samples.begin();
+        //-----------------------------------------------------------------------------------------------
+        const double timeDelta = recordBack.first        - recordFront.first;
+        const double dataDelta = recordBack.second.data_ - recordFront.second.data_;
+
+        if (!numeric::isNull(timeDelta))
+            if (dataDelta > 0) //may be negative if user cancels copying
+                return zen::filesizeToShortString(zen::Int64(dataDelta * 1000 / timeDelta)) + _("/sec");
+    }
+    return wxT("-"); //fallback
+}
+
+
+/*
+class for calculation of remaining time:
+----------------------------------------
+"filesize |-> time" is an affine linear function f(x) = z_1 + z_2 x
+
+For given n measurements, sizes x_0, ..., x_n and times f_0, ..., f_n, the function f (as a polynom of degree 1) can be lineary approximated by
+
+z_1 = (r - s * q / p) / ((n + 1) - s * s / p)
+z_2 = (q - s * z_1) / p = (r - (n + 1) z_1) / s
+
+with
+p := x_0^2 + ... + x_n^2
+q := f_0 x_0 + ... + f_n x_n
+r := f_0 + ... + f_n
+s := x_0 + ... + x_n
+
+=> the time to process N files with amount of data D is:    N * z_1 + D * z_2
+
+Problem:
+--------
+Times f_0, ..., f_n can be very small so that precision of the PC clock is poor.
+=> Times have to be accumulated to enhance precision:
+Copying of m files with sizes x_i and times f_i (i = 1, ..., m) takes sum_i f(x_i) := m * z_1 + z_2 * sum x_i = sum f_i
+With X defined as the accumulated sizes and F the accumulated times this gives: (in theory...)
+m * z_1 + z_2 * X = F   <=>
+z_1 + z_2 * X / m = F / m
+
+=> we obtain a new (artificial) measurement with size X / m and time F / m to be used in the linear approximation above
+
+
+Statistics::Statistics(const int totalObjectCount, const double totalDataAmount, const unsigned recordCount) :
+        objectsTotal(totalObjectCount),
+        dataTotal(totalDataAmount),
+        recordsMax(recordCount),
+        objectsLast(0),
+        dataLast(0),
+        timeLast(wxGetLocalTimeMillis()),
+        z1_current(0),
+        z2_current(0),
+        dummyRecordPresent(false) {}
+
+
+wxString Statistics::getRemainingTime(const int objectsCurrent, const double dataCurrent)
+{
+    //add new measurement point
+    const int m = objectsCurrent - objectsLast;
+    if (m != 0)
+    {
+        objectsLast = objectsCurrent;
+
+        const double X = dataCurrent - dataLast;
+        dataLast = dataCurrent;
+
+        const zen::Int64 timeCurrent = wxGetLocalTimeMillis();
+        const double F = (timeCurrent - timeLast).ToDouble();
+        timeLast = timeCurrent;
+
+        record newEntry;
+        newEntry.x_i = X / m;
+        newEntry.f_i = F / m;
+
+        //remove dummy record
+        if (dummyRecordPresent)
+        {
+            measurements.pop_back();
+            dummyRecordPresent = false;
+        }
+
+        //insert new record
+        measurements.push_back(newEntry);
+        if (measurements.size() > recordsMax)
+            measurements.pop_front();
+    }
+    else //dataCurrent increased without processing new objects:
+    {    //modify last measurement until m != 0
+        const double X = dataCurrent - dataLast; //do not set dataLast, timeLast variables here, but write dummy record instead
+        if (!isNull(X))
+        {
+            const zen::Int64 timeCurrent = wxGetLocalTimeMillis();
+            const double F = (timeCurrent - timeLast).ToDouble();
+
+            record modifyEntry;
+            modifyEntry.x_i = X;
+            modifyEntry.f_i = F;
+
+            //insert dummy record
+            if (!dummyRecordPresent)
+            {
+                measurements.push_back(modifyEntry);
+                if (measurements.size() > recordsMax)
+                    measurements.pop_front();
+                dummyRecordPresent = true;
+            }
+            else //modify dummy record
+                measurements.back() = modifyEntry;
+        }
+    }
+
+    //calculate remaining time based on stored measurement points
+    double p = 0;
+    double q = 0;
+    double r = 0;
+    double s = 0;
+    for (std::list<record>::const_iterator i = measurements.begin(); i != measurements.end(); ++i)
+    {
+        const double x_i = i->x_i;
+        const double f_i = i->f_i;
+        p += x_i * x_i;
+        q += f_i * x_i;
+        r += f_i;
+        s += x_i;
+    }
+
+    if (!isNull(p))
+    {
+        const double n   = measurements.size();
+        const double tmp = (n - s * s / p);
+
+        if (!isNull(tmp) && !isNull(s))
+        {
+            const double z1 = (r - s * q / p) / tmp;
+            const double z2 = (r - n * z1) / s;    //not (n + 1) here, since n already is the number of measurements
+
+            //refresh current values for z1, z2
+            z1_current = z1;
+            z2_current = z2;
+        }
+    }
+
+    return formatRemainingTime((objectsTotal - objectsCurrent) * z1_current + (dataTotal - dataCurrent) * z2_current);
+}
+
+*/