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.
29 from threading import BoundedSemaphore
31 globalsem = BoundedSemaphore()
33 # special constant that tells vserver to keep its existing settings
34 KEEP_LIMIT = vserver.VC_LIM_KEEP
36 # populate the sliver/vserver specific default allocations table,
37 # which is used to look for slice attributes
38 DEFAULT_ALLOCATION = {}
39 for rlimit in vserver.RLIMITS.keys():
41 DEFAULT_ALLOCATION["%s_min"%rlim]=KEEP_LIMIT
42 DEFAULT_ALLOCATION["%s_soft"%rlim]=KEEP_LIMIT
43 DEFAULT_ALLOCATION["%s_hard"%rlim]=KEEP_LIMIT
45 class Sliver_VS(accounts.Account, vserver.VServer):
46 """This class wraps vserver.VServer to make its interface closer to what we need."""
49 TYPE = 'sliver.VServer'
50 _init_disk_info_sem = globalsem
52 def __init__(self, rec):
53 logger.verbose ('initing Sliver_VS with name=%s'%rec['name'])
55 vserver.VServer.__init__(self, rec['name'],logfile='/var/log/nm')
56 except Exception, err:
57 if not isinstance(err, vserver.NoSuchVServer):
58 # Probably a bad vserver or vserver configuration file
59 logger.log_exc(self.name)
60 logger.log('%s: recreating bad vserver' % rec['name'])
61 self.destroy(rec['name'])
62 self.create(rec['name'], rec['vref'])
63 vserver.VServer.__init__(self, rec['name'],logfile='/var/log/nm')
68 self.slice_id = rec['slice_id']
69 self.disk_usage_initialized = False
70 self.initscriptchanged = False
73 _root_context_arch=None
75 def root_context_arch():
76 if not Sliver_VS._root_context_arch:
77 Sliver_VS._root_context_arch=commands.getoutput("uname -i")
78 return Sliver_VS._root_context_arch
81 def personality (arch):
83 if arch.find("64")>=0:
88 def create(name, vref = None):
89 logger.verbose('Sliver_VS:create - name=%s'%name)
93 ### locating the right slicefamily
94 # this is a first draft, and more a proof of concept thing
95 # the idea is to parse vref for dash-separated wishes,
96 # and to project these against the defaults
97 # so e.g. if the default slice family (as found in /etc/planetlab/slicefamily)
98 # is planetlab-f8-i386, then here is what we get
99 # vref=x86_64 -> vuseradd -t planetlab-f8-x86_64
100 # vref=centos5 -> vuseradd -t planetlab-centos5-i386
101 # vref=centos5-onelab -> vuseradd -t onelab-centos5-i386
102 # vref=planetflow -> vuseradd -t planetflow-f8-i386
103 # vref=x86_64-planetflow -> vuseradd -t planetflow-f8-x86_64
106 default=file("/etc/planetlab/slicefamily").read().strip()
107 (pldistro,fcdistro,arch) = default.split("-")
109 known_archs = [ 'i386', 'x86_64' ]
110 known_fcdistros = [ 'f8', 'f9', 'centos5' ]
111 # from the slice attribute: cut dashes and try to figure the meaning
112 slice_wishes = vref.split("-")
113 for wish in slice_wishes:
114 if wish in known_archs:
116 elif wish in known_fcdistros:
122 refname="-".join( (pldistro,fcdistro,arch) )
124 # check the template exists -- there's probably a better way..
125 if not os.path.isdir ("/vservers/.vref/%s"%refname):
126 logger.verbose("%s (%s) : vref %s not found, using default %s"%(
127 name,vref,refname,default))
129 # reset so arch is right
130 (pldistro,fcdistro,arch) = default.split("-")
131 # could check again, but as we have /etc/slicefamily
132 # there's probably no /vservers/.vref/default
135 # have not found slicefamily
136 logger.verbose("%s (%s): legacy node - using fallback vrefname 'default'"%(name,vref))
142 logger.log("%s (%s) : unexpected error follows - using 'default'"%(name,vref))
143 logger.log(traceback.format_exc())
147 logger.log_call('/usr/sbin/vuseradd', '-t', refname, name)
148 # export slicename to the slice in /etc/slicename
149 file('/vservers/%s/etc/slicename' % name, 'w').write(name)
150 # set personality: only if needed (if arch's differ)
151 if Sliver_VS.root_context_arch() != arch:
152 file('/etc/vservers/%s/personality' % name, 'w').write(Sliver_VS.personality(arch))
153 logger.log('%s: set personality to %s'%(name,Sliver_VS.personality(arch)))
156 def destroy(name): logger.log_call('/usr/sbin/vuserdel', name)
158 def configure(self, rec):
159 new_rspec = rec['_rspec']
160 if new_rspec != self.rspec:
161 self.rspec = new_rspec
164 new_initscript = rec['initscript']
165 if new_initscript != self.initscript:
166 self.initscript = new_initscript
167 logger.log('%s: installing initscript' % self.name)
168 def install_initscript():
169 flags = os.O_WRONLY | os.O_CREAT | os.O_TRUNC
170 fd = os.open('/etc/rc.vinit', flags, 0755)
171 os.write(fd, new_initscript)
174 self.chroot_call(install_initscript)
175 self.initscriptchanged = True
176 except: logger.log_exc(self.name)
178 accounts.Account.configure(self, rec) # install ssh keys
180 def start(self, delay=0):
181 if self.rspec['enabled'] > 0:
182 logger.log('%s: starting in %d seconds' % (self.name, delay))
184 child_pid = os.fork()
186 # VServer.start calls fork() internally,
187 # so just close the nonstandard fds and fork once to avoid creating zombies
188 tools.close_nonstandard_fds()
189 vserver.VServer.start(self)
191 else: os.waitpid(child_pid, 0)
192 else: logger.log('%s: not starting, is not enabled' % self.name)
193 self.initscriptchanged = False
196 logger.log('%s: stopping' % self.name)
197 vserver.VServer.stop(self)
199 def set_resources(self):
200 disk_max = self.rspec['disk_max']
201 logger.log('%s: setting max disk usage to %d KiB' % (self.name, disk_max))
202 try: # if the sliver is over quota, .set_disk_limit will throw an exception
203 if not self.disk_usage_initialized:
204 self.vm_running = False
205 logger.log('%s: computing disk usage: beginning' % self.name)
206 Sliver_VS._init_disk_info_sem.acquire()
207 try: self.init_disk_info()
208 finally: Sliver_VS._init_disk_info_sem.release()
209 logger.log('%s: computing disk usage: ended' % self.name)
210 self.disk_usage_initialized = True
211 vserver.VServer.set_disklimit(self, max(disk_max, self.disk_blocks))
213 logger.log('%s: failed to set max disk usage' % self.name)
214 logger.log_exc(self.name)
216 # get/set the min/soft/hard values for all of the vserver
217 # related RLIMITS. Note that vserver currently only
218 # implements support for hard limits.
219 for limit in vserver.RLIMITS.keys():
221 minimum = self.rspec['%s_min'%type]
222 soft = self.rspec['%s_soft'%type]
223 hard = self.rspec['%s_hard'%type]
224 update = self.set_rlimit(limit, hard, soft, minimum)
226 logger.log('%s: setting rlimit %s to (%d, %d, %d)'
227 % (self.name, type, hard, soft, minimum))
229 self.set_capabilities_config(self.rspec['capabilities'])
230 if self.rspec['capabilities']:
231 logger.log('%s: setting capabilities to %s' % (self.name, self.rspec['capabilities']))
233 cpu_pct = self.rspec['cpu_pct']
234 cpu_share = self.rspec['cpu_share']
236 if self.rspec['enabled'] > 0:
238 logger.log('%s: setting cpu reservation to %d%%' % (self.name, cpu_pct))
243 logger.log('%s: setting cpu share to %d' % (self.name, cpu_share))
247 self.set_sched_config(cpu_pct, cpu_share)
248 # if IP address isn't set (even to 0.0.0.0), sliver won't be able to use network
249 if self.rspec['ip_addresses'] != '0.0.0.0':
250 logger.log('%s: setting IP address(es) to %s' % \
251 (self.name, self.rspec['ip_addresses']))
252 self.set_ipaddresses_config(self.rspec['ip_addresses'])
254 if self.is_running():
255 logger.log("%s: Setting name to %s" % (self.name, self.slice_id),2)
256 self.setname(self.slice_id)
258 if False: # Does not work properly yet.
259 if self.have_limits_changed():
260 logger.log('%s: limits have changed --- restarting' % self.name)
262 while self.is_running() and stopcount > 0:
266 stopcount = stopcount - 1
269 else: # tell vsh to disable remote login by setting CPULIMIT to 0
270 logger.log('%s: disabling remote login' % self.name)
271 self.set_sched_config(0, 0)