import xen.lowlevel.xc import xen.lowlevel.xs import string import time import qmemman_algo import os from guihelpers import notify_error_qubes_manager, clear_error_qubes_manager no_progress_msg="VM refused to give back requested memory" slow_memset_react_msg="VM didn't give back all requested memory" class DomainState: def __init__(self, id): self.meminfo = None #dictionary of memory info read from client self.memory_actual = None #the current memory size self.memory_maximum = None #the maximum memory size self.mem_used = None #used memory, computed based on meminfo self.id = id #domain id self.last_target = 0 #the last memset target self.no_progress = False #no react to memset self.slow_memset_react = False #slow react to memset (after few tries still above target) class SystemState: def __init__(self): self.domdict = {} self.xc = xen.lowlevel.xc.xc() self.xs = xen.lowlevel.xs.xs() self.BALOON_DELAY = 0.1 self.XEN_FREE_MEM_LEFT = 50*1024*1024 self.XEN_FREE_MEM_MIN = 25*1024*1024 self.ALL_PHYS_MEM = self.xc.physinfo()['total_memory']*1024 def add_domain(self, id): self.domdict[id] = DomainState(id) def del_domain(self, id): self.domdict.pop(id) def get_free_xen_memory(self): return self.xc.physinfo()['free_memory']*1024 # hosts = self.xend_session.session.xenapi.host.get_all() # host_record = self.xend_session.session.xenapi.host.get_record(hosts[0]) # host_metrics_record = self.xend_session.session.xenapi.host_metrics.get_record(host_record["metrics"]) # ret = host_metrics_record["memory_free"] # return long(ret) #refresh information on memory assigned to all domains def refresh_memactual(self): for domain in self.xc.domain_getinfo(): id = str(domain['domid']) if self.domdict.has_key(id): self.domdict[id].memory_actual = domain['mem_kb']*1024 self.domdict[id].memory_maximum = self.xs.read('', '/local/domain/%s/memory/static-max' % str(id)) if not self.domdict[id].memory_maximum: self.domdict[id].memory_maximum = self.ALL_PHYS_MEM # the previous line used to be # self.domdict[id].memory_maximum = domain['maxmem_kb']*1024 # but domain['maxmem_kb'] changes in self.mem_set as well, and this results in # the memory never increasing # in fact, the only possible case of nonexisting memory/static-max is dom0 # see #307 def clear_outdated_error_markers(self): # Clear outdated errors for i in self.domdict.keys(): if self.domdict[i].slow_memset_react and \ self.domdict[i].memory_actual <= self.domdict[i].last_target + self.XEN_FREE_MEM_LEFT/4: dom_name = self.xs.read('', '/local/domain/%s/name' % str(i)) clear_error_qubes_manager(dom_name, slow_memset_react_msg) self.domdict[i].slow_memset_react = False if self.domdict[i].no_progress and \ self.domdict[i].memory_actual <= self.domdict[i].last_target + self.XEN_FREE_MEM_LEFT/4: dom_name = self.xs.read('', '/local/domain/%s/name' % str(i)) clear_error_qubes_manager(dom_name, no_progress_msg) self.domdict[i].no_progress = False #the below works (and is fast), but then 'xm list' shows unchanged memory value def mem_set(self, id, val): print 'mem-set domain', id, 'to', val self.domdict[id].last_target = val #can happen in the middle of domain shutdown #apparently xc.lowlevel throws exceptions too try: self.xc.domain_setmaxmem(int(id), int(val/1024) + 1024) # LIBXL_MAXMEM_CONSTANT=1024 self.xc.domain_set_target_mem(int(id), int(val/1024)) except: pass self.xs.write('', '/local/domain/' + id + '/memory/target', str(int(val/1024))) def mem_set_obsolete(self, id, val): uuid = self.domdict[id].uuid if val >= 2**31: print 'limiting memory from ', val, 'to maxint because of xml-rpc lameness' val = 2**31 - 1 print 'mem-set domain', id, 'to', val try: self.xend_session.session.xenapi.VM.set_memory_dynamic_max_live(uuid, val) self.xend_session.session.xenapi.VM.set_memory_dynamic_min_live(uuid, val) #can happen in the middle of domain shutdown except XenAPI.Failure: pass # this is called at the end of ballooning, when we have Xen free mem already # make sure that past mem_set will not decrease Xen free mem def inhibit_balloon_up(self): for i in self.domdict.keys(): dom = self.domdict[i] if dom.memory_actual is not None and dom.memory_actual + 200*1024 < dom.last_target: print "Preventing balloon up to", dom.last_target self.mem_set(i, dom.memory_actual) #perform memory ballooning, across all domains, to add "memsize" to Xen free memory def do_balloon(self, memsize): MAX_TRIES = 20 niter = 0 prev_memory_actual = None for i in self.domdict.keys(): self.domdict[i].no_progress = False print "do_balloon start" while True: self.refresh_memactual() xenfree = self.get_free_xen_memory() print 'got xenfree=', xenfree if xenfree >= memsize + self.XEN_FREE_MEM_MIN: self.inhibit_balloon_up() return True if prev_memory_actual is not None: for i in prev_memory_actual.keys(): if prev_memory_actual[i] == self.domdict[i].memory_actual: #domain not responding to memset requests, remove it from donors self.domdict[i].no_progress = True print 'domain', i, 'stuck at', self.domdict[i].memory_actual memset_reqs = qmemman_algo.balloon(memsize + self.XEN_FREE_MEM_LEFT - xenfree, self.domdict) print 'requests:', memset_reqs if niter > MAX_TRIES or len(memset_reqs) == 0: return False prev_memory_actual = {} for i in memset_reqs: dom, mem = i self.mem_set(dom, mem) prev_memory_actual[dom] = self.domdict[dom].memory_actual time.sleep(self.BALOON_DELAY) niter = niter + 1 def refresh_meminfo(self, domid, untrusted_meminfo_key): qmemman_algo.refresh_meminfo_for_domain(self.domdict[domid], untrusted_meminfo_key) self.do_balance() #is the computed balance request big enough ? #so that we do not trash with small adjustments def is_balance_req_significant(self, memset_reqs, xenfree): total_memory_transfer = 0 MIN_TOTAL_MEMORY_TRANSFER = 150*1024*1024 MIN_MEM_CHANGE_WHEN_UNDER_PREF = 15*1024*1024 # If xenfree to low, return immediately if self.XEN_FREE_MEM_LEFT - xenfree > MIN_MEM_CHANGE_WHEN_UNDER_PREF: return True for rq in memset_reqs: dom, mem = rq last_target = self.domdict[dom].last_target memory_change = mem - last_target total_memory_transfer += abs(memory_change) pref = qmemman_algo.prefmem(self.domdict[dom]) if last_target > 0 and last_target < pref and memory_change > MIN_MEM_CHANGE_WHEN_UNDER_PREF: print 'dom', dom, 'is below pref, allowing balance' return True return total_memory_transfer + abs(xenfree - self.XEN_FREE_MEM_LEFT) > MIN_TOTAL_MEMORY_TRANSFER def print_stats(self, xenfree, memset_reqs): for i in self.domdict.keys(): if self.domdict[i].meminfo is not None: print 'dom' , i, 'act/pref', self.domdict[i].memory_actual, qmemman_algo.prefmem(self.domdict[i]) print 'xenfree=', xenfree, 'balance req:', memset_reqs def do_balance(self): if os.path.isfile('/var/run/qubes/do-not-membalance'): return self.refresh_memactual() self.clear_outdated_error_markers() xenfree = self.get_free_xen_memory() memset_reqs = qmemman_algo.balance(xenfree - self.XEN_FREE_MEM_LEFT, self.domdict) if not self.is_balance_req_significant(memset_reqs, xenfree): return self.print_stats(xenfree, memset_reqs) prev_memactual = {} for i in self.domdict.keys(): prev_memactual[i] = self.domdict[i].memory_actual for rq in memset_reqs: dom, mem = rq # Force to always have at least 0.9*self.XEN_FREE_MEM_LEFT (some # margin for rounding errors). Before giving memory to # domain, ensure that others have gived it back. # If not - wait a little. ntries = 5 while self.get_free_xen_memory() - (mem - self.domdict[dom].memory_actual) < 0.9*self.XEN_FREE_MEM_LEFT: time.sleep(self.BALOON_DELAY) ntries -= 1 if ntries <= 0: # Waiting haven't helped; Find which domain get stuck and # abort balance (after distributing what we have) self.refresh_memactual() for rq2 in memset_reqs: dom2, mem2 = rq2 if dom2 == dom: # All donors have been procesed break # allow some small margin if self.domdict[dom2].memory_actual > self.domdict[dom2].last_target + self.XEN_FREE_MEM_LEFT/4: # VM didn't react to memory request at all, remove from donors if prev_memactual[dom2] == self.domdict[dom2].memory_actual: print 'dom %s didnt react to memory request (holds %d, requested balloon down to %d)' % (dom2, self.domdict[dom2].memory_actual, mem2) self.domdict[dom2].no_progress = True dom_name = self.xs.read('', '/local/domain/%s/name' % str(dom2)) if dom_name is not None: notify_error_qubes_manager(str(dom_name), no_progress_msg) else: print 'dom %s still hold more memory than have assigned (%d > %d)' % (dom2, self.domdict[dom2].memory_actual, mem2) self.domdict[dom2].slow_memset_react = True dom_name = self.xs.read('', '/local/domain/%s/name' % str(dom2)) if dom_name is not None: notify_error_qubes_manager(str(dom_name), slow_memset_react_msg) self.mem_set(dom, self.get_free_xen_memory() + self.domdict[dom].memory_actual - self.XEN_FREE_MEM_LEFT) return self.mem_set(dom, mem) # for i in self.domdict.keys(): # print 'domain ', i, ' meminfo=', self.domdict[i].meminfo, 'actual mem', self.domdict[i].memory_actual # print 'domain ', i, 'actual mem', self.domdict[i].memory_actual # print 'xen free mem', self.get_free_xen_memory()