Re: [KVM-AUTOTEST PATCH 2/2] Add KSM test

[Dor Laor <dlaor@redhat.com>]

On 08/31/2009 12:48 PM, Lukáš Doktor wrote:
> This is an actual KSM test.
>
> It allows to test merging resp splitting the pages in serial, parallel
> or both. Also you can specify an overcommit ratio for KSM overcommit
> testing.
>
> We were forced to destroy all previous defined vms and to create them
> inside the test (similar to stress_boot), because we don't know how many
> machines will be required during the vm preparation.
>
> Second nasty thing is filling the memory by the guests. We didn't find
> better way to test filled memory without the python(kvm-autotest) fall.
> This version continue filling until a small reserve than destroy
> previous machines and let the actual machine finish the work.

This is quite helpful /me has few ideas for enhancements/simplification, 
you might have implemented some of them, but I think it can improve ksm 
coverage testing:
[btw: for all newbies ksm is in F12 now]

1. Guest tool that creates the memory pressure
    Instead of writing your own tool in 'c' and open specific tcp port
    to talk with it I suggest the following:
    a. Use ssh into the guest. Autotest already support it.
    b. Basically, instead of your program you can use some existing tool.
       If you mount tmpfs you can create files on this directory using
       dd and it will fill the guest ram, like dd if=/dev/urandom
       of=MOUNT_POINT bs=4k count=x.
       It might be simpler than a new binary but python code might be ok
       too.
2. Measure the exact activity of ksm
    Let's cancel guest swap (swapoff -a) and write specific values to
    the guest ram. For instance, if you have 10 VMs and you allocate
    512M in each of them with the same random value in each of their
    pages, you would expect to merge 10 * 512M / 4k pages into a single
    page in the host.

3. KSM test cases.
    a. standard case - like above - merge many pages into one.
       Change the value from all random into the same one and check
       convergence.
    b. Worse case - ksm use red-black trees for ram. The trees
       use the entire page as a key. So putting the same value in the
       first 4000 bytes and afterwards random value in the last 96 bytes
       of each page will cause ksm scanner to work really hard.
       Keep, changing the last bytes during the test duration.
    c. Change ksm scan speed and memory limits.
       We need to test that too.
    d. KVM swap support and ksm
       Over commit the host memory using scenario a by 200%
       At once, write random values to all pages of the guests.
       It will cause the host to swap the VM pages.
       The test is actually testing kvm host swap support.

HTH,
Dor


>
> Signed-off-by: Lukáš Doktor<ldoktor@redhat.com>
> Signed-off-by: Jiří Župka<jzupka@redhat.com>
> ---
>    client/tests/kvm/kvm.py               |    2 +
>    client/tests/kvm/kvm_tests.cfg.sample |   17 +
>    client/tests/kvm/kvm_tests.py         |  548
> +++++++++++++++++++++++++++++++++
>    3 files changed, 567 insertions(+), 0 deletions(-)
>
> diff --git a/client/tests/kvm/kvm.py b/client/tests/kvm/kvm.py
> index 4930e80..b9839df 100644
> --- a/client/tests/kvm/kvm.py
> +++ b/client/tests/kvm/kvm.py
> @@ -53,6 +53,8 @@ class kvm(test.test):
>                    "yum_update":   test_routine("kvm_tests",
> "run_yum_update"),
>                    "autotest":     test_routine("kvm_tests", "run_autotest"),
>                    "kvm_install":  test_routine("kvm_install",
> "run_kvm_install"),
> +                "ksm":
> +                                test_routine("kvm_tests", "run_ksm"),
>                    "linux_s3":     test_routine("kvm_tests", "run_linux_s3"),
>                    "stress_boot":  test_routine("kvm_tests",
> "run_stress_boot"),
>                    "timedrift":    test_routine("kvm_tests",
> "run_timedrift"),
> diff --git a/client/tests/kvm/kvm_tests.cfg.sample
> b/client/tests/kvm/kvm_tests.cfg.sample
> index a83ef9b..f4a41b9 100644
> --- a/client/tests/kvm/kvm_tests.cfg.sample
> +++ b/client/tests/kvm/kvm_tests.cfg.sample
> @@ -100,6 +100,23 @@ variants:
>                    test_name = disktest
>                    test_control_file = disktest.control
>
> +    - ksm:
> +        # Don't preprocess any vms as we need to change it's params
> +        vms = ''
> +        image_snapshot = yes
> +        kill_vm_gracefully = no
> +        type = ksm
> +        variants:
> +            - ratio_3:
> +                ksm_ratio = 3
> +            - ratio_10:
> +                ksm_ratio = 10
> +        variants:
> +            - serial
> +                ksm_test_size = "serial"
> +            - paralel
> +                ksm_test_size = "paralel"
> +
>        - linux_s3:     install setup
>            type = linux_s3
>
> diff --git a/client/tests/kvm/kvm_tests.py b/client/tests/kvm/kvm_tests.py
> index b100269..ada4c6b 100644
> --- a/client/tests/kvm/kvm_tests.py
> +++ b/client/tests/kvm/kvm_tests.py
> @@ -462,6 +462,554 @@ def run_yum_update(test, params, env):
>
>        session.close()
>
> +def run_ksm(test, params, env):
> +    """
> +    Test how KSM (Kernel Shared Memory) act with more than physical
> memory is
> +    used. In second part is also tested, how KVM can handle the situation,
> +    when the host runs out of memory (expected is to pause the guest
> system,
> +    wait until some process returns the memory and bring the guest back
> to life)
> +
> +    @param test: kvm test object.
> +    @param params: Dictionary with test parameters.
> +    @param env: Dictionary with the test wnvironment.
> +    """
> +    # We are going to create the main VM so we use kvm_preprocess functions
> +    # FIXME: not a nice thing
> +    import kvm_preprocessing
> +    import random
> +    import socket
> +    import select
> +    import math
> +
> +    class allocator_com:
> +        """
> +        This class is used for communication with the allocator
> +        """
> +        def __init__(self, vm, _port, _host='127.0.0.1'):
> +            self.vm = vm
> +            self.PORT = _port
> +            self.HOST = _host
> +            self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
> +            self.isConnect = False
> +
> +        def __str__(self):
> +            return self.vm + ":" + self.HOST + ":" + str(self.PORT)
> +
> +        def connect(self):
> +            print self
> +            logging.debug("ALLOC: connect to %s", self.vm)
> +            try:
> +                self.socket.connect((self.HOST, self.PORT))
> +            except:
> +                raise error.TestFail("ALLOC: Could not establish the "\
> +                                     "communication with %s" % (self.vm))
> +            self.isConnect = True
> +
> +        def isConnected(self):
> +            return self.isConnect;
> +
> +        def readsize(self):
> +            read,write,error =
> select.select([self.socket.fileno()],[],[],0.5)
> +            size = 0
> +            if (self.socket.fileno() in read):
> +                data = self.socket.recv(1);
> +                size = "";
> +                while data[0] != ':':
> +                    size = size + data[0]
> +                    data = self.socket.recv(1)
> +            return int(size)
> +
> +        def _recv(self):
> +            msg = ""
> +            read, write, error = select.select([self.socket.fileno()],\
> +                                               [], [], 0.5)
> +            if (self.socket.fileno() in read):
> +                size = self.readsize()
> +                msg = self.socket.recv(size)
> +                if (len(msg)<  size):
> +                    raise error.TestFail("ALLOC: Could not recive the
> message")
> +
> +            logging.debug("ALLOC: output '%s' from %s" % (msg, self.vm))
> +            return msg
> +
> +        def recv(self, wait=1, loops=20):
> +            out = ""
> +            log = ""
> +            while not out.startswith("PASS") and not
> out.startswith("FAIL"):
> +                logging.debug("Sleep(%d)" % (wait))
> +                time.sleep(wait)
> +                log += out
> +                out = self._recv()
> +
> +                if loops == 0:
> +                    logging.error(repr(out))
> +                    raise error.TestFail("Command wasn't finished until
> DL")
> +                loops = loops - 1
> +
> +            if not out.startswith("PASS"):
> +                logging.error("Allocator failed on guest %s\nAttaching
> the"\
> +                              "recent log"  % (self.vm))
> +                raise error.TestFail(log)
> +
> +            return out
> +
> +
> +        def send(self, command, data=""):
> +            msg = str(len(command) + len(data) + 3)
> +            msg += ":" + command + ":" + data + ";"
> +            logging.debug("ALLOC: execute %s on %s" %(repr(msg), self.vm))
> +            try:
> +                self.socket.sendall(msg)
> +            except:
> +                raise error.TestFail("ALLOC: Could not send the message")
> +
> +        def disconnect(self):
> +            logging.debug("ALLOC: disconnect")
> +            self.send("exit")
> +            self.recv()
> +            time.sleep(5)
> +            self.socket.close()
> +            self.isConnect = False
> +
> +    def get_stat(lvms):
> +        """
> +        Get statistics in format:
> +        Host: memfree = XXXM; Guests memsh = {XXX,XXX,...}
> +
> +        @params lvms: List of VMs
> +        """
> +        if not isinstance(lvms, list):
> +            raise error.TestError("get_stat: parameter have to be
> proper list")
> +
> +        try:
> +            stat = "Host: memfree = "
> +            stat += str(int(os.popen("cat /proc/meminfo | grep MemFree")\
> +                                     .readline().split()[1]) / 1024) +
> "M;"
> +            stat += "swapfree = "
> +            stat += str(int(os.popen("cat /proc/meminfo | grep SwapFree")\
> +                                     .readline().split()[1]) / 1024) +
> "M;"
> +        except:
> +            raise error.TestFail("Could not fetch free memory info")
> +
> +
> +        stat += "Guests memsh = {"
> +        for vm in lvms:
> +            try:
> +                cmd = "cat /proc/%d/statm" % vm.pid
> +                shm = int(os.popen(cmd).readline().split()[2])
> +                # statm stores informations in pages, recalculate to MB
> +                shm = shm * 4 / 1024
> +                stat += "%dM; " % (shm)
> +            except:
> +                raise error.TestError("Could not fetch shmem info from
> proc")
> +        stat = stat[0:-2] + "}"
> +        return stat
> +
> +
> +
> +
> +
> +    logging.info("Starting phase 0: Initialization")
> +    # host_reserve: mem reserve keept for the host system to run
> +    host_reserve = 256
> +    # guest_reserve: mem reserve which is not used by allocator on the
> guests
> +    guest_reserve = 256
> +    max_alloc = 10
> +    max_vms = params.get("max_vms")
> +    if max_vms:
> +        max_vms = int(max_vms)
> +    else:
> +        max_vms = 2
> +    overcommit = params.get("ksm_overcommit_ratio")
> +    if overcommit:
> +        overcommit = float(overcommit)
> +    else:
> +        overcommit = 2.0
> +    # vmsc: count of all used VMs
> +    vmsc = int(overcommit) + 1
> +    vmsc = max(vmsc, max_vms)
> +
> +    if (params['ksm_test_size'] == "paralel") :
> +        host_mem = (int(os.popen("grep MemTotal: /proc/meminfo")\
> +                       .readline().split()[1]) / 1024 - host_reserve)
> +        vmsc = 1
> +        overcommit = 1
> +        mem = host_mem
> +        # 32bit system adjustment
> +        if not params['image_name'].endswith("64"):
> +            logging.debug("Probably i386 guest architecture, "\
> +                          "max allocator mem = 2G")
> +            # Guest can have more than 2G but kvm mem + 1MB (allocator
> itself) can't
> +            if (host_mem>  2048):
> +                mem = 2047
> +
> +
> +        if os.popen("uname -i").readline().startswith("i386"):
> +            logging.debug("Host is i386 architecture, max guest mem is 2G")
> +            # Guest system with qemu overhead (64M) can't have more than 2G
> +            if mem>  2048 - 64:
> +                mem = 2048 - 64
> +
> +    else:
> +        host_mem = (int(os.popen("grep MemTotal: /proc/meminfo")\
> +                       .readline().split()[1]) / 1024 - host_reserve)
> +        # mem: Memory of the guest systems. Maximum must be less than
> amount of the
> +        # host's physical ram
> +        mem = int(overcommit * host_mem / vmsc)
> +
> +        # 32bit system adjustment
> +        if not params['image_name'].endswith("64"):
> +            logging.debug("Probably i386 guest architecture, "\
> +                          "max allocator mem = 2G")
> +            # Guest can have more than 2G but kvm mem + 1MB (allocator
> itself) can't
> +            if mem-guest_reserve-1>  2048:
> +                vmsc =
> int(math.ceil((host_mem*overcommit)/(2048.0+guest_reserve)))
> +                mem = int(math.floor(host_mem*overcommit/vmsc))
> +
> +        if os.popen("uname -i").readline().startswith("i386"):
> +            logging.debug("Host is i386 architecture, max guest mem is 2G")
> +            # Guest system with qemu overhead (64M) can't have more than 2G
> +            if mem>  2048 - 64:
> +                vmsc = int(math.ceil((host_mem*overcommit)/(2048 - 64.0)))
> +                mem = int(math.floor(host_mem*overcommit/vmsc))
> +
> +
> +    logging.info("overcommit = %f" % (overcommit))
> +    logging.info("true overcommit = %f " % (float(vmsc*mem) /
> float(host_mem)))
> +    logging.info("host mem = %dM" % (host_mem))
> +    logging.info("mem = %dM" % (mem))
> +    logging.info("swap = %dM" %\
> +                 (int(os.popen("cat /proc/meminfo | grep SwapTotal")\
> +                              .readline().split()[1]) / 1024))
> +    logging.info("max_vms = %d" % (max_vms))
> +    logging.info("vmsc = %d" % (vmsc))
> +
> +    # Generate unique keys for random series
> +    skeys = []
> +    dkeys = []
> +    for i in range(0, max(vmsc, max_alloc)):
> +        key = "%03s" % (random.randrange(0,999))
> +        while key in skeys:
> +            key = "%03s" % (random.randrange(0,999))
> +        skeys.append(key)
> +
> +        key = "%03s" % (random.randrange(0,999))
> +        while key in dkeys:
> +            key = "%03s" % (random.randrange(0,999))
> +        dkeys.append(key)
> +
> +    lvms = []
> +    lsessions = []
> +    lallocators = []
> +    alloc_port = 31284
> +
> +    # As we don't know the number and memory amount of VMs in advance,
> we need
> +    # to specify and create them here (FIXME: not a nice thing)
> +    params['mem'] = mem
> +    params['vms'] = params.get("main_vm")
> +    # ksm_size: amount of memory used by allocator
> +    ksm_size = mem - guest_reserve
> +    logging.info("ksm_size = %dM" % (ksm_size))
> +
> +
> +    params['redirs'] += ' alloc0'
> +    params['guest_port_alloc0'] = str(alloc_port)
> +
> +    if (params['ksm_test_size'] == "paralel") :
> +        for j in range(1, max_alloc):
> +            params['redirs'] += ' alloc' + str(j)
> +            params['guest_port_alloc' + str(j)] = str(alloc_port + j)
> +
> +    # Creating of the first guest
> +    kvm_preprocessing.preprocess_vm(test, params, env, params['vms'])
> +    lvms.append(kvm_utils.env_get_vm(env, params.get("main_vm")))
> +    if not lvms[0]:
> +        raise error.TestError("VM object not found in environment")
> +    if not lvms[0].is_alive():
> +        raise error.TestError("VM seems to be dead; Test requires a
> living VM")
> +
> +    logging.info("Booting the first guest %s" % lvms[0].name)
> +
> +    lsessions.append(kvm_utils.wait_for(lvms[0].ssh_login, 360, 0, 2))
> +    if not lsessions[0]:
> +        raise error.TestFail("Could not log into first guest")
> +
> +
> +    lallocators.append(allocator_com(lvms[0].name,
> lvms[0].redirs[alloc_port]))
> +    if not lallocators[0]:
> +        raise error.TestFail("Could not create allocator_com class for
> vm1")
> +
> +
> +
> +    # Creating of other guest systems
> +    for i in range(1, vmsc):
> +        vm_name = "vm" + str(i + 1)
> +        # Last VM is later used to run more allocators simultaneously
> +        """for j in range(1, max_alloc):
> +            params['redirs'] += ' alloc' + str(j)
> +            params['guest_port_alloc' + str(j)] = str(alloc_port + j)"""
> +
> +        lvms.append(lvms[0].clone(vm_name, params))
> +        kvm_utils.env_register_vm(env, vm_name, lvms[i])
> +        params['vms'] += " " + vm_name
> +
> +        logging.info("Booting guest %s" % lvms[i].name)
> +        if not lvms[i].create():
> +            raise error.TestFail("Cannot create VM %s" % lvms[i].name)
> +        if not lvms[i].is_alive():
> +            raise error.TestError("VM %s seems to be dead; Test
> requires a"\
> +                                  "living VM" % lvms[i].name)
> +
> +        lsessions.append(kvm_utils.wait_for(lvms[i].ssh_login, 360, 0, 2))
> +        if not lsessions[i]:
> +            raise error.TestFail("Could not log into guest %s" %
> lvms[i].name)
> +
> +        lallocators.append(allocator_com(lvms[i].name,\
> +                                         lvms[i].redirs[alloc_port]))
> +        if not lallocators[i]:
> +            raise error.TestFail("Could not create allocator_com class
> for %s"\
> +                                 % (lvms[i].name))
> +
> +
> +    # Let systems take a rest :-)
> +    time.sleep(vmsc * 2)
> +    logging.info(get_stat(lvms))
> +
> +    # Copy the allocator.c into guests
> +    pwd = os.path.join(os.environ['AUTODIR'],'tests/kvm')
> +    vksmd_src = os.path.join(pwd, "allocator.c")
> +    dst_dir = "/tmp"
> +    for vm in lvms:
> +        if not vm.scp_to_remote(vksmd_src, dst_dir):
> +            raise error.TestFail("Remote scp failed %s" % (vm.name))
> +    logging.info("Phase 0 =>  passed")
> +
> +    def phase_1():
> +        """ Inicialize virtual machine """
> +        logging.info("Starting phase 1: filling with 0")
> +        logging.info("Preparing the guests and fill in pages by zero")
> +        for session in lsessions:
> +            vm = lvms[lsessions.index(session)]
> +            allocator = lallocators[lsessions.index(session)]
> +            # Build the test suite
> +            ret = session.get_command_status("gcc -o /tmp/allocator "\
> +                                             "/tmp/allocator.c",\
> +                                             timeout=300)
> +            if ret == None or ret:
> +                raise error.TestFail("Failed to build vksmd in the %s"\
> +                                     % (vm.name))
> +
> +            # Start the daemon
> +            ret = session.get_command_status("/tmp/allocator %d %d" %
> (ksm_size,\
> +
> alloc_port))
> +            if ret == None:
> +                raise error.TestFail("Could not run vksmd in guest %s"\
> +                                     % (vm.name))
> +            if ret:
> +                raise error.TestFail("Could not run vksmd in %s errno: %d"\
> +                                      % (vm.name, ret))
> +
> +            ret = session.get_command_status("iptables -F;"\
> +                                             "iptables -P INPUT ACCEPT;")
> +
> +            allocator.connect()
> +            allocator.recv((ksm_size / 200), 100)
> +
> +            # Let kksmd works (until shared mem rich expected value)
> +            shm = 0
> +            i = 0
> +            cmd = "cat /proc/%d/statm" % vm.pid
> +            while shm<  ksm_size:
> +                if i>  64:
> +                    logging.info(get_stat(lvms))
> +                    raise error.TestError("SHM didn't merged the memory
> until "\
> +					  "the DL")
> +                logging.debug("Sleep(%d)" % (ksm_size / 200))
> +                time.sleep(ksm_size / 200)
> +                try:
> +                    shm = int(os.popen(cmd).readline().split()[2])
> +                    shm = shm * 4 / 1024
> +                    i = i + 1
> +                except:
> +                    raise error.TestError("Could not fetch shmem info
> from "
> +					  "the /proc")
> +
> +        # Keep some reserve
> +        time.sleep(ksm_size / 200)
> +
> +        # Set allocator keys
> +        for i in range(0, vmsc):
> +            lallocators[i].send("init", "%s%s" % (skeys[i], dkeys[i]))
> +            lallocators[i].recv(1, 10)
> +        logging.info(get_stat(lvms))
> +        logging.info("Phase 1 =>  passed")
> +
> +    def phase_2():
> +        """ Separate first guest memory by generate a special random
> series """
> +        logging.info("Starting phase 2: Split the pages on the first
> guest")
> +
> +        lallocators[0].send("srandom")
> +        out = lallocators[0].recv(ksm_size / 500, 50)
> +        out = int(out.split()[4])
> +        logging.info("PERFORMANCE: %dMB * 1000 / %dms = %dMB/s"\
> +                     % (ksm_size, out, (ksm_size * 1000 / out)))
> +        logging.info(get_stat(lvms))
> +        logging.info("Phase 2 =>  passed")
> +
> +    def phase_3():
> +        """ Sequentional split of pages on guests up to memory limit """
> +        logging.info("Starting phase 3a: Sequentional split of pages on
> guests up "\
> +                     "to memory limit")
> +        last_vm = 0
> +        for i in range(1, vmsc):
> +            vm = lvms[i]
> +            session = lsessions[i]
> +            allocator = lallocators[i]
> +
> +            allocator.send("srandom")
> +            out = ""
> +            while not out.startswith("PASS") and not
> out.startswith("FAIL"):
> +                free_mem = int(os.popen("grep MemFree /proc/meminfo")\
> +                             .readline().split()[1])
> +                logging.debug("FreeMem = %d" % (free_mem))
> +                # We need to keep some memory for python to run.
> +                if free_mem<  32000:
> +                    logging.debug("Only %s free memory, killing 0 - %d
> hosts"\
> +                                  % (free_mem, (i-1)))
> +                    for j in range(0, i):
> +                        lvms[j].destroy(gracefully = False)
> +                    last_vm = i
> +                    break
> +                out = allocator._recv()
> +            if last_vm != 0:
> +                break
> +
> +        allocator.recv(mem / 500, 50)
> +        logging.info("Memory filled by the guest %s" % (vm.name))
> +        logging.info("Phase 3a =>  passed")
> +
> +        """ Check if memory in max loading guest is allright"""
> +        logging.info("Starting phase 3b")
> +        allocator.send("srverify")
> +        allocator.recv(mem / 200, 50)
> +        allocator.disconnect()
> +        # We are going to use the last VM later
> +        if i != (vmsc):
> +            session.close()
> +            vm.destroy(gracefully = False)
> +            for i in range(last_vm + 1, vmsc):
> +                lallocators[i].send("verify")
> +                lallocators[i].recv(mem / 200, 50)
> +                lallocators[i].disconnect()
> +                # We are going to use the last VM later
> +                if i != (vmsc - 1):
> +                    lsessions[i].close()
> +                    lvms[i].destroy(gracefully = False)
> +        logging.info(get_stat([lvms[i]]))
> +        logging.info("Phase 3b =>  passed")
> +
> +    def phase_4():
> +        """ Paralel page spliting """
> +        logging.info("Phase 4: Paralel page spliting")
> +        # We have to wait until allocator is finished (it waits 5
> seconds to clean
> +        # the socket
> +
> +        session = lsessions[0]
> +        vm = lvms[0]
> +
> +        ret = session.get_command_status("gcc -o /tmp/allocator "\
> +                                             "/tmp/allocator.c",\
> +                                             timeout=300)
> +        if ret == None or ret:
> +            raise error.TestFail("Failed to build vksmd in the %s"\
> +                                  % (vm.name))
> +
> +        for all in lallocators:
> +            if all.isConnected():
> +                all.disconnect()
> +
> +        del lallocators[:]
> +        ret = session.get_command_status("iptables -F;"\
> +                                    "iptables -P INPUT ACCEPT;")
> +
> +        for i in range(0, max_alloc):
> +            ret = session.get_command_status("/tmp/allocator %d %d"
> +                                   % (ksm_size / max_alloc, alloc_port
> + i))
> +            if ret == None:
> +                raise error.TestFail("Could not run vksmd in guest %s"\
> +                                     % (vm.name))
> +            if ret:
> +                raise error.TestFail("Could not run allocator in %s
> errno: %d"\
> +                                     % (vm.name, ret))
> +
> +            lallocators.append(allocator_com(vm.name,\
> +                                             vm.redirs[alloc_port + i]))
> +            if not lallocators[i]:
> +                raise error.TestFail("Could not create allocator_com
> class for"\
> +				     " %s" % (vm.name))
> +
> +        logging.info("Phase 4a: Simultaneous merging")
> +        for i in range(0, max_alloc):
> +            lallocators[i].connect()
> +
> +        for i in range(0, max_alloc):
> +            lallocators[i].recv((ksm_size / 200), 100)
> +        # Wait until kksmd merges the pages (3 x ksm_size / 3)
> +        shm = 0
> +        i = 0
> +        cmd = "cat /proc/%d/statm" % vm.pid
> +        while shm<  ksm_size:
> +            if i>  64:
> +                logging.info(get_stat(lvms))
> +                raise error.TestError("SHM didn't merged the memory
> until DL")
> +            logging.debug("Sleep(%d)" % (ksm_size / 200))
> +            time.sleep(ksm_size / 200)
> +            try:
> +                shm = int(os.popen(cmd).readline().split()[2])
> +                shm = shm * 4 / 1024
> +            except:
> +                raise error.TestError("Could not fetch shmem info from
> proc")
> +        logging.info(get_stat([vm]))
> +
> +
> +        logging.info("Phases 4b: Simultaneous spliting")
> +        # Set keys
> +        for i in range(0, max_alloc):
> +            lallocators[i].send("init", "%s%s" % (skeys[i], dkeys[i]))
> +            lallocators[i].recv(1, 10)
> +
> +        # Actual splitting
> +        for i in range(0, max_alloc):
> +            lallocators[i].send("srandom")
> +
> +        for i in range(0, max_alloc):
> +            out = lallocators[i].recv(ksm_size / 500, 50)
> +            out = int(out.split()[4])
> +            logging.info("PERFORMANCE: %dMB * 1000 / %dms = %dMB/s"\
> +                         % (ksm_size, out, (ksm_size * 1000 / out /
> max_alloc)))
> +        logging.info(get_stat([vm]))
> +
> +        logging.info("Phase 4c: Simultaneous verification")
> +        for i in range(0, max_alloc):
> +            lallocators[i].send("srverify")
> +        for i in range(0, max_alloc):
> +            lallocators[i].recv(mem / 200, 50)
> +        logging.info(get_stat([vm]))
> +
> +        logging.info("Phase 4 =>  passed")
> +        # Clean-up
> +        for i in range(0, max_alloc):
> +            lallocators[i].disconnect()
> +        session.close()
> +        vm.destroy(gracefully = False)
> +
> +    if params['ksm_test_size'] == "paralel":
> +        phase_4()
> +    elif params['ksm_test_size'] == "serial":
> +        phase_1()
> +        phase_2()
> +        phase_3()
> +
>
>    def run_linux_s3(test, params, env):
>        """