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 logger.log('%s: installing initscript' % self.name)
159 def install_initscript():
160 flags = os.O_WRONLY | os.O_CREAT | os.O_TRUNC
161 fd = os.open('/etc/rc.vinit', flags, 0755)
162 os.write(fd, new_initscript)
165 self.chroot_call(install_initscript)
166 self.initscriptchanged = True
167 except: logger.log_exc(self.name)
169 accounts.Account.configure(self, rec) # install ssh keys
171 def start(self, delay=0):
172 if self.rspec['enabled'] > 0:
173 logger.log('%s: starting in %d seconds' % (self.name, delay))
175 child_pid = os.fork()
177 # VServer.start calls fork() internally,
178 # so just close the nonstandard fds and fork once to avoid creating zombies
179 tools.close_nonstandard_fds()
180 vserver.VServer.start(self)
182 else: os.waitpid(child_pid, 0)
183 else: logger.log('%s: not starting, is not enabled' % self.name)
184 self.initscriptchanged = False
187 logger.log('%s: stopping' % self.name)
188 vserver.VServer.stop(self)
190 def set_resources(self):
191 disk_max = self.rspec['disk_max']
192 logger.log('%s: setting max disk usage to %d KiB' % (self.name, disk_max))
193 try: # if the sliver is over quota, .set_disk_limit will throw an exception
194 if not self.disk_usage_initialized:
195 self.vm_running = False
196 Sliver_VS._init_disk_info_sem.acquire()
197 logger.log('%s: computing disk usage: beginning' % self.name)
198 try: self.init_disk_info()
199 finally: Sliver_VS._init_disk_info_sem.release()
200 logger.log('%s: computing disk usage: ended' % self.name)
201 self.disk_usage_initialized = True
202 vserver.VServer.set_disklimit(self, max(disk_max, self.disk_blocks))
204 logger.log('%s: failed to set max disk usage' % self.name)
205 logger.log_exc(self.name)
207 # get/set the min/soft/hard values for all of the vserver
208 # related RLIMITS. Note that vserver currently only
209 # implements support for hard limits.
210 for limit in vserver.RLIMITS.keys():
212 minimum = self.rspec['%s_min'%type]
213 soft = self.rspec['%s_soft'%type]
214 hard = self.rspec['%s_hard'%type]
215 update = self.set_rlimit(limit, hard, soft, minimum)
217 logger.log('%s: setting rlimit %s to (%d, %d, %d)'
218 % (self.name, type, hard, soft, minimum))
220 self.set_capabilities_config(self.rspec['capabilities'])
221 if self.rspec['capabilities']:
222 logger.log('%s: setting capabilities to %s' % (self.name, self.rspec['capabilities']))
224 cpu_pct = self.rspec['cpu_pct']
225 cpu_share = self.rspec['cpu_share']
227 if self.rspec['enabled'] > 0:
229 logger.log('%s: setting cpu reservation to %d%%' % (self.name, cpu_pct))
234 logger.log('%s: setting cpu share to %d' % (self.name, cpu_share))
238 self.set_sched_config(cpu_pct, cpu_share)
239 # if IP address isn't set (even to 0.0.0.0), sliver won't be able to use network
240 if self.rspec['ip_addresses'] != '0.0.0.0':
241 logger.log('%s: setting IP address(es) to %s' % \
242 (self.name, self.rspec['ip_addresses']))
243 self.set_ipaddresses_config(self.rspec['ip_addresses'])
245 if self.is_running():
246 logger.log("%s: Setting name to %s" % (self.name, self.slice_id),2)
247 self.setname(self.slice_id)
249 if False: # Does not work properly yet.
250 if self.have_limits_changed():
251 logger.log('%s: limits have changed --- restarting' % self.name)
253 while self.is_running() and stopcount > 0:
257 stopcount = stopcount - 1
260 else: # tell vsh to disable remote login by setting CPULIMIT to 0
261 logger.log('%s: disabling remote login' % self.name)
262 self.set_sched_config(0, 0)