3 There are a couple of tricky things going on here. First, the kernel
4 needs disk usage information in order to enforce the quota. However,
5 determining disk usage redundantly strains the disks. Thus, the
6 Sliver_VS.disk_usage_initialized flag is used to determine whether
7 this initialization has been made.
9 Second, it's not currently possible to set the scheduler parameters
10 for a sliver unless that sliver has a running process. /bin/vsh helps
11 us out by reading the configuration file so that it can set the
12 appropriate limits after entering the sliver context. Making the
13 syscall that actually sets the parameters gives a harmless error if no
14 process is running. Thus we keep vm_running on when setting scheduler
15 parameters so that set_sched_params() always makes the syscall, and we
16 don't have to guess if there is a running process or not.
28 # special constant that tells vserver to keep its existing settings
29 KEEP_LIMIT = vserver.VC_LIM_KEEP
31 # populate the sliver/vserver specific default allocations table,
32 # which is used to look for slice attributes
33 DEFAULT_ALLOCATION = {}
34 for rlimit in vserver.RLIMITS.keys():
36 DEFAULT_ALLOCATION["%s_min"%rlim]=KEEP_LIMIT
37 DEFAULT_ALLOCATION["%s_soft"%rlim]=KEEP_LIMIT
38 DEFAULT_ALLOCATION["%s_hard"%rlim]=KEEP_LIMIT
40 class Sliver_VS(accounts.Account, vserver.VServer):
41 """This class wraps vserver.VServer to make its interface closer to what we need."""
44 TYPE = 'sliver.VServer'
45 _init_disk_info_sem = tools.NMLock("/var/run/nm-disk-info.lock")
47 def __init__(self, rec):
48 logger.verbose ('initing Sliver_VS with name=%s'%rec['name'])
50 vserver.VServer.__init__(self, rec['name'],logfile='/var/log/nm')
51 except Exception, err:
52 if not isinstance(err, vserver.NoSuchVServer):
53 # Probably a bad vserver or vserver configuration file
54 logger.log_exc(self.name)
55 logger.log('%s: recreating bad vserver' % rec['name'])
56 self.destroy(rec['name'])
57 self.create(rec['name'], rec['vref'])
58 vserver.VServer.__init__(self, rec['name'],logfile='/var/log/nm')
63 self.disk_usage_initialized = False
64 self.initscriptchanged = False
68 def create(name, vref = None):
69 logger.verbose('Sliver_VS:create - name=%s'%name)
73 ### locating the right slicefamily
74 # this is a first draft, and more a proof of concept thing
75 # the idea is to parse vref for dash-separated wishes,
76 # and to project these against the defaults
77 # however for cases like when vref is 'planetflow', if we do not understand
78 # any of the wishes we take vref as is
79 # this could be improved by having the vserver-reference init script be a bit smarter
80 # so we could take planetflow as the pldistro part here
83 default=file("/etc/planetlab/defaultvref").read()
84 (pldistro,fcdistro,arch) = default.split("-")
85 # from the slice attribute: cut dashes and try to figure the meaning
86 slice_wishes = vref.split("-")
87 for wish in slice_wishes:
88 if wish == "i386" or wish == "x86_64":
90 elif wish == "planetlab" or wish == "onelab" or wish == "vini":
92 elif wish == "f8" or wish == "centos5" :
95 # if we find something like e.g. planetflow, use it as-is
101 refname="-".join( (pldistro,fcdistro,arch) )
102 # check the templates exists -- there's probably a better way..
103 if not os.path.isdir ("/vservers/.vref/%s"%refname):
104 log.verbose("%s (%s) : vref %s not found, using default %s"%(
105 name,vref,refname,default))
108 # have not found defaultvref
109 logger.verbose("%s (%s): using fallback vrefname 'default'"%(name,vref))
114 logger.log("%s (%s) : unexpected error follows - using 'default'"%(
116 logger.log(traceback.format_exc())
118 logger.log_call('/usr/sbin/vuseradd', '-t', refname, name)
119 open('/vservers/%s/etc/slicename' % name, 'w').write(name)
122 def destroy(name): logger.log_call('/usr/sbin/vuserdel', name)
124 def configure(self, rec):
125 new_rspec = rec['_rspec']
126 if new_rspec != self.rspec:
127 self.rspec = new_rspec
130 new_initscript = rec['initscript']
131 if new_initscript != self.initscript:
132 self.initscript = new_initscript
133 logger.log('%s: installing initscript' % self.name)
134 def install_initscript():
135 flags = os.O_WRONLY | os.O_CREAT | os.O_TRUNC
136 fd = os.open('/etc/rc.vinit', flags, 0755)
137 os.write(fd, new_initscript)
140 self.chroot_call(install_initscript)
141 self.initscriptchanged = True
142 except: logger.log_exc(self.name)
144 accounts.Account.configure(self, rec) # install ssh keys
146 def start(self, delay=0):
147 if self.rspec['enabled'] > 0:
148 logger.log('%s: starting in %d seconds' % (self.name, delay))
150 child_pid = os.fork()
152 # VServer.start calls fork() internally, so just close the nonstandard fds and fork once to avoid creating zombies
153 tools.close_nonstandard_fds()
154 vserver.VServer.start(self, True)
156 else: os.waitpid(child_pid, 0)
157 else: logger.log('%s: not starting, is not enabled' % self.name)
158 self.initscriptchanged = False
161 logger.log('%s: stopping' % self.name)
162 vserver.VServer.stop(self)
164 def set_resources(self):
165 disk_max = self.rspec['disk_max']
166 logger.log('%s: setting max disk usage to %d KiB' % (self.name, disk_max))
167 try: # if the sliver is over quota, .set_disk_limit will throw an exception
168 if not self.disk_usage_initialized:
169 self.vm_running = False
170 logger.log('%s: computing disk usage: beginning' % self.name)
171 Sliver_VS._init_disk_info_sem.acquire()
172 try: self.init_disk_info()
173 finally: Sliver_VS._init_disk_info_sem.release()
174 logger.log('%s: computing disk usage: ended' % self.name)
175 self.disk_usage_initialized = True
176 vserver.VServer.set_disklimit(self, max(disk_max, self.disk_blocks))
178 logger.log('%s: failed to set max disk usage' % self.name)
179 logger.log_exc(self.name)
181 # get/set the min/soft/hard values for all of the vserver
182 # related RLIMITS. Note that vserver currently only
183 # implements support for hard limits.
184 for limit in vserver.RLIMITS.keys():
186 minimum = self.rspec['%s_min'%type]
187 soft = self.rspec['%s_soft'%type]
188 hard = self.rspec['%s_hard'%type]
189 update = self.set_rlimit(limit, hard, soft, minimum)
191 logger.log('%s: setting rlimit %s to (%d, %d, %d)'
192 % (self.name, type, hard, soft, minimum))
194 self.set_capabilities_config(self.rspec['capabilities'])
195 if self.rspec['capabilities']:
196 logger.log('%s: setting capabilities to %s' % (self.name, self.rspec['capabilities']))
198 if False: # this code was commented out before
199 # N.B. net_*_rate are in kbps because of XML-RPC maxint
200 # limitations, convert to bps which is what bwlimit.py expects.
201 net_limits = (self.rspec['net_min_rate'] * 1000,
202 self.rspec['net_max_rate'] * 1000,
203 self.rspec['net_i2_min_rate'] * 1000,
204 self.rspec['net_i2_max_rate'] * 1000,
205 self.rspec['net_share'])
206 logger.log('%s: setting net limits to %s bps' % (self.name, net_limits[:-1]))
207 logger.log('%s: setting net share to %d' % (self.name, net_limits[-1]))
208 self.set_bwlimit(*net_limits)
210 cpu_pct = self.rspec['cpu_pct']
211 cpu_share = self.rspec['cpu_share']
213 if self.rspec['enabled'] > 0:
215 logger.log('%s: setting cpu reservation to %d%%' % (self.name, cpu_pct))
220 logger.log('%s: setting cpu share to %d' % (self.name, cpu_share))
224 self.set_sched_config(cpu_pct, cpu_share)
225 # if IP address isn't set (even to 0.0.0.0), sliver won't be able to use network
226 if self.rspec['ip_addresses'] != '0.0.0.0':
227 logger.log('%s: setting IP address(es) to %s' % (self.name, self.rspec['ip_addresses']))
228 self.set_ipaddresses_config(self.rspec['ip_addresses'])
230 if False: # Does not work properly yet.
231 if self.have_limits_changed():
232 logger.log('%s: limits have changed --- restarting' % self.name)
234 while self.is_running() and stopcount > 0:
238 stopcount = stopcount - 1
241 else: # tell vsh to disable remote login by setting CPULIMIT to 0
242 logger.log('%s: disabling remote login' % self.name)
243 self.set_sched_config(0, 0)