diff --git a/import-layers/yocto-poky/meta/lib/buildstats.py b/import-layers/yocto-poky/meta/lib/buildstats.py
new file mode 100644
index 0000000..c5d4c73
--- /dev/null
+++ b/import-layers/yocto-poky/meta/lib/buildstats.py
@@ -0,0 +1,158 @@
+# Implements system state sampling. Called by buildstats.bbclass.
+# Because it is a real Python module, it can hold persistent state,
+# like open log files and the time of the last sampling.
+
+import time
+import re
+import bb.event
+
+class SystemStats:
+    def __init__(self, d):
+        bn = d.getVar('BUILDNAME')
+        bsdir = os.path.join(d.getVar('BUILDSTATS_BASE'), bn)
+        bb.utils.mkdirhier(bsdir)
+
+        self.proc_files = []
+        for filename, handler in (
+                ('diskstats', self._reduce_diskstats),
+                ('meminfo', self._reduce_meminfo),
+                ('stat', self._reduce_stat),
+        ):
+            # The corresponding /proc files might not exist on the host.
+            # For example, /proc/diskstats is not available in virtualized
+            # environments like Linux-VServer. Silently skip collecting
+            # the data.
+            if os.path.exists(os.path.join('/proc', filename)):
+                # In practice, this class gets instantiated only once in
+                # the bitbake cooker process.  Therefore 'append' mode is
+                # not strictly necessary, but using it makes the class
+                # more robust should two processes ever write
+                # concurrently.
+                destfile = os.path.join(bsdir, '%sproc_%s.log' % ('reduced_' if handler else '', filename))
+                self.proc_files.append((filename, open(destfile, 'ab'), handler))
+        self.monitor_disk = open(os.path.join(bsdir, 'monitor_disk.log'), 'ab')
+        # Last time that we sampled /proc data resp. recorded disk monitoring data.
+        self.last_proc = 0
+        self.last_disk_monitor = 0
+        # Minimum number of seconds between recording a sample. This
+        # becames relevant when we get called very often while many
+        # short tasks get started. Sampling during quiet periods
+        # depends on the heartbeat event, which fires less often.
+        self.min_seconds = 1
+
+        self.meminfo_regex = re.compile(b'^(MemTotal|MemFree|Buffers|Cached|SwapTotal|SwapFree):\s*(\d+)')
+        self.diskstats_regex = re.compile(b'^([hsv]d.|mtdblock\d|mmcblk\d|cciss/c\d+d\d+.*)$')
+        self.diskstats_ltime = None
+        self.diskstats_data = None
+        self.stat_ltimes = None
+
+    def close(self):
+        self.monitor_disk.close()
+        for _, output, _ in self.proc_files:
+            output.close()
+
+    def _reduce_meminfo(self, time, data):
+        """
+        Extracts 'MemTotal', 'MemFree', 'Buffers', 'Cached', 'SwapTotal', 'SwapFree'
+        and writes their values into a single line, in that order.
+        """
+        values = {}
+        for line in data.split(b'\n'):
+            m = self.meminfo_regex.match(line)
+            if m:
+                values[m.group(1)] = m.group(2)
+        if len(values) == 6:
+            return (time,
+                    b' '.join([values[x] for x in
+                               (b'MemTotal', b'MemFree', b'Buffers', b'Cached', b'SwapTotal', b'SwapFree')]) + b'\n')
+
+    def _diskstats_is_relevant_line(self, linetokens):
+        if len(linetokens) != 14:
+            return False
+        disk = linetokens[2]
+        return self.diskstats_regex.match(disk)
+
+    def _reduce_diskstats(self, time, data):
+        relevant_tokens = filter(self._diskstats_is_relevant_line, map(lambda x: x.split(), data.split(b'\n')))
+        diskdata = [0] * 3
+        reduced = None
+        for tokens in relevant_tokens:
+            # rsect
+            diskdata[0] += int(tokens[5])
+            # wsect
+            diskdata[1] += int(tokens[9])
+            # use
+            diskdata[2] += int(tokens[12])
+        if self.diskstats_ltime:
+            # We need to compute information about the time interval
+            # since the last sampling and record the result as sample
+            # for that point in the past.
+            interval = time - self.diskstats_ltime
+            if interval > 0:
+                sums = [ a - b for a, b in zip(diskdata, self.diskstats_data) ]
+                readTput = sums[0] / 2.0 * 100.0 / interval
+                writeTput = sums[1] / 2.0 * 100.0 / interval
+                util = float( sums[2] ) / 10 / interval
+                util = max(0.0, min(1.0, util))
+                reduced = (self.diskstats_ltime, (readTput, writeTput, util))
+
+        self.diskstats_ltime = time
+        self.diskstats_data = diskdata
+        return reduced
+
+
+    def _reduce_nop(self, time, data):
+        return (time, data)
+
+    def _reduce_stat(self, time, data):
+        if not data:
+            return None
+        # CPU times {user, nice, system, idle, io_wait, irq, softirq} from first line
+        tokens = data.split(b'\n', 1)[0].split()
+        times = [ int(token) for token in tokens[1:] ]
+        reduced = None
+        if self.stat_ltimes:
+            user = float((times[0] + times[1]) - (self.stat_ltimes[0] + self.stat_ltimes[1]))
+            system = float((times[2] + times[5] + times[6]) - (self.stat_ltimes[2] + self.stat_ltimes[5] + self.stat_ltimes[6]))
+            idle = float(times[3] - self.stat_ltimes[3])
+            iowait = float(times[4] - self.stat_ltimes[4])
+
+            aSum = max(user + system + idle + iowait, 1)
+            reduced = (time, (user/aSum, system/aSum, iowait/aSum))
+
+        self.stat_ltimes = times
+        return reduced
+
+    def sample(self, event, force):
+        now = time.time()
+        if (now - self.last_proc > self.min_seconds) or force:
+            for filename, output, handler in self.proc_files:
+                with open(os.path.join('/proc', filename), 'rb') as input:
+                    data = input.read()
+                    if handler:
+                        reduced = handler(now, data)
+                    else:
+                        reduced = (now, data)
+                    if reduced:
+                        if isinstance(reduced[1], bytes):
+                            # Use as it is.
+                            data = reduced[1]
+                        else:
+                            # Convert to a single line.
+                            data = (' '.join([str(x) for x in reduced[1]]) + '\n').encode('ascii')
+                        # Unbuffered raw write, less overhead and useful
+                        # in case that we end up with concurrent writes.
+                        os.write(output.fileno(),
+                                 ('%.0f\n' % reduced[0]).encode('ascii') +
+                                 data +
+                                 b'\n')
+            self.last_proc = now
+
+        if isinstance(event, bb.event.MonitorDiskEvent) and \
+           ((now - self.last_disk_monitor > self.min_seconds) or force):
+            os.write(self.monitor_disk.fileno(),
+                     ('%.0f\n' % now).encode('ascii') +
+                     ''.join(['%s: %d\n' % (dev, sample.total_bytes - sample.free_bytes)
+                              for dev, sample in event.disk_usage.items()]).encode('ascii') +
+                     b'\n')
+            self.last_disk_monitor = now