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 from threading import BoundedSemaphore
30 globalsem = BoundedSemaphore()
32 # special constant that tells vserver to keep its existing settings
33 KEEP_LIMIT = vserver.VC_LIM_KEEP
35 # populate the sliver/vserver specific default allocations table,
36 # which is used to look for slice attributes
37 DEFAULT_ALLOCATION = {}
38 for rlimit in vserver.RLIMITS.keys():
40 DEFAULT_ALLOCATION["%s_min"%rlim]=KEEP_LIMIT
41 DEFAULT_ALLOCATION["%s_soft"%rlim]=KEEP_LIMIT
42 DEFAULT_ALLOCATION["%s_hard"%rlim]=KEEP_LIMIT
44 class Sliver_VS(accounts.Account, vserver.VServer):
45 """This class wraps vserver.VServer to make its interface closer to what we need."""
48 TYPE = 'sliver.VServer'
49 _init_disk_info_sem = globalsem
51 def __init__(self, rec):
52 logger.verbose ('initing Sliver_VS with name=%s'%rec['name'])
54 vserver.VServer.__init__(self, rec['name'],logfile='/var/log/nm')
55 except Exception, err:
56 if not isinstance(err, vserver.NoSuchVServer):
57 # Probably a bad vserver or vserver configuration file
58 logger.log_exc(self.name)
59 logger.log('%s: recreating bad vserver' % rec['name'])
60 self.destroy(rec['name'])
61 self.create(rec['name'], rec['vref'])
62 vserver.VServer.__init__(self, rec['name'],logfile='/var/log/nm')
67 self.slice_id = rec['slice_id']
68 self.disk_usage_initialized = False
69 self.initscriptchanged = False
73 def create(name, vref = None):
74 logger.verbose('Sliver_VS:create - name=%s'%name)
78 ### locating the right slicefamily
79 # this is a first draft, and more a proof of concept thing
80 # the idea is to parse vref for dash-separated wishes,
81 # and to project these against the defaults
82 # so e.g. if the default slice family (as found in /etc/planetlab/slicefamily)
83 # is planetlab-f8-i386, then here is what we get
84 # vref=x86_64 -> vuseradd -t planetlab-f8-x86_64
85 # vref=centos5 -> vuseradd -t planetlab-centos5-i386
86 # vref=centos5-onelab -> vuseradd -t onelab-centos5-i386
87 # vref=planetflow -> vuseradd -t planetflow-f8-i386
88 # vref=x86_64-planetflow -> vuseradd -t planetflow-f8-x86_64
91 default=file("/etc/planetlab/slicefamily").read().strip()
92 (pldistro,fcdistro,arch) = default.split("-")
94 known_archs = [ 'i386', 'x86_64' ]
95 known_fcdistros = [ 'f8', 'f9', 'centos5' ]
96 # from the slice attribute: cut dashes and try to figure the meaning
97 slice_wishes = vref.split("-")
98 for wish in slice_wishes:
99 if wish in known_archs:
101 elif wish in known_fcdistros:
107 refname="-".join( (pldistro,fcdistro,arch) )
109 # check the template exists -- there's probably a better way..
110 if not os.path.isdir ("/vservers/.vref/%s"%refname):
111 logger.verbose("%s (%s) : vref %s not found, using default %s"%(
112 name,vref,refname,default))
114 # reset so arch is right
115 (pldistro,fcdistro,arch) = default.split("-")
116 # could check again, but as we have /etc/slicefamily
117 # there's probably no /vservers/.vref/default
120 # have not found slicefamily
121 logger.verbose("%s (%s): legacy node - using fallback vrefname 'default'"%(name,vref))
127 logger.log("%s (%s) : unexpected error follows - using 'default'"%(name,vref))
128 logger.log(traceback.format_exc())
132 def personality (arch):
133 personality="linux32"
134 if arch.find("64")>=0:
135 personality="linux64"
138 logger.log_call('/usr/sbin/vuseradd', '-t', refname, name)
139 # export slicename to the slice in /etc/slicename
140 file('/vservers/%s/etc/slicename' % name, 'w').write(name)
141 # set personality: only if needed (if arch's differ)
142 if tools.root_context_arch() != arch:
143 file('/etc/vservers/%s/personality' % name, 'w').write(personality(arch))
144 logger.log('%s: set personality to %s'%(name,personality(arch)))
147 def destroy(name): logger.log_call('/usr/sbin/vuserdel', name)
149 def configure(self, rec):
150 new_rspec = rec['_rspec']
151 if new_rspec != self.rspec:
152 self.rspec = new_rspec
155 new_initscript = rec['initscript']
156 if new_initscript != self.initscript:
157 self.initscript = new_initscript
158 self.initscriptchanged = True
160 accounts.Account.configure(self, rec) # install ssh keys
162 def start(self, delay=0):
163 if self.rspec['enabled'] > 0:
164 logger.log('%s: starting in %d seconds' % (self.name, delay))
166 # VServer.start calls fork() internally,
167 # so just close the nonstandard fds and fork once to avoid creating zombies
168 child_pid = os.fork()
170 if self.initscriptchanged:
171 logger.log('%s: installing initscript' % self.name)
172 def install_initscript():
173 flags = os.O_WRONLY | os.O_CREAT | os.O_TRUNC
174 fd = os.open('/etc/rc.vinit', flags, 0755)
175 os.write(fd, self.initscript)
178 self.chroot_call(install_initscript)
179 except: logger.log_exc(self.name)
180 tools.close_nonstandard_fds()
181 vserver.VServer.start(self)
184 os.waitpid(child_pid, 0)
185 self.initscriptchanged = False
186 else: logger.log('%s: not starting, is not enabled' % self.name)
189 logger.log('%s: stopping' % self.name)
190 vserver.VServer.stop(self)
192 def is_running(self):
193 return vserver.VServer.is_running(self)
195 def set_resources(self):
196 disk_max = self.rspec['disk_max']
197 logger.log('%s: setting max disk usage to %d KiB' % (self.name, disk_max))
198 try: # if the sliver is over quota, .set_disk_limit will throw an exception
199 if not self.disk_usage_initialized:
200 self.vm_running = False
201 Sliver_VS._init_disk_info_sem.acquire()
202 logger.log('%s: computing disk usage: beginning' % self.name)
203 try: self.init_disk_info()
204 finally: Sliver_VS._init_disk_info_sem.release()
205 logger.log('%s: computing disk usage: ended' % self.name)
206 self.disk_usage_initialized = True
207 vserver.VServer.set_disklimit(self, max(disk_max, self.disk_blocks))
209 logger.log('%s: failed to set max disk usage' % self.name)
210 logger.log_exc(self.name)
212 # get/set the min/soft/hard values for all of the vserver
213 # related RLIMITS. Note that vserver currently only
214 # implements support for hard limits.
215 for limit in vserver.RLIMITS.keys():
217 minimum = self.rspec['%s_min'%type]
218 soft = self.rspec['%s_soft'%type]
219 hard = self.rspec['%s_hard'%type]
220 update = self.set_rlimit(limit, hard, soft, minimum)
222 logger.log('%s: setting rlimit %s to (%d, %d, %d)'
223 % (self.name, type, hard, soft, minimum))
225 self.set_capabilities_config(self.rspec['capabilities'])
226 if self.rspec['capabilities']:
227 logger.log('%s: setting capabilities to %s' % (self.name, self.rspec['capabilities']))
229 cpu_pct = self.rspec['cpu_pct']
230 cpu_share = self.rspec['cpu_share']
232 if self.rspec['enabled'] > 0:
234 logger.log('%s: setting cpu reservation to %d%%' % (self.name, cpu_pct))
239 logger.log('%s: setting cpu share to %d' % (self.name, cpu_share))
243 self.set_sched_config(cpu_pct, cpu_share)
244 # if IP address isn't set (even to 0.0.0.0), sliver won't be able to use network
245 if self.rspec['ip_addresses'] != '0.0.0.0':
246 logger.log('%s: setting IP address(es) to %s' % \
247 (self.name, self.rspec['ip_addresses']))
248 self.set_ipaddresses_config(self.rspec['ip_addresses'])
250 if self.is_running():
251 logger.log("%s: Setting name to %s" % (self.name, self.slice_id),2)
252 self.setname(self.slice_id)
254 if False: # Does not work properly yet.
255 if self.have_limits_changed():
256 logger.log('%s: limits have changed --- restarting' % self.name)
258 while self.is_running() and stopcount > 0:
262 stopcount = stopcount - 1
265 else: # tell vsh to disable remote login by setting CPULIMIT to 0
266 logger.log('%s: disabling remote login' % self.name)
267 self.set_sched_config(0, 0)