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.
27 from threading import BoundedSemaphore
29 globalsem = BoundedSemaphore()
31 # special constant that tells vserver to keep its existing settings
32 KEEP_LIMIT = vserver.VC_LIM_KEEP
34 # populate the sliver/vserver specific default allocations table,
35 # which is used to look for slice attributes
36 DEFAULT_ALLOCATION = {}
37 for rlimit in vserver.RLIMITS.keys():
39 DEFAULT_ALLOCATION["%s_min"%rlim]=KEEP_LIMIT
40 DEFAULT_ALLOCATION["%s_soft"%rlim]=KEEP_LIMIT
41 DEFAULT_ALLOCATION["%s_hard"%rlim]=KEEP_LIMIT
43 class Sliver_VS(accounts.Account, vserver.VServer):
44 """This class wraps vserver.VServer to make its interface closer to what we need."""
47 TYPE = 'sliver.VServer'
48 _init_disk_info_sem = globalsem
50 def __init__(self, rec):
51 logger.verbose ('initing Sliver_VS with name=%s'%rec['name'])
53 vserver.VServer.__init__(self, rec['name'],logfile='/var/log/nm')
54 except Exception, err:
55 if not isinstance(err, vserver.NoSuchVServer):
56 # Probably a bad vserver or vserver configuration file
57 logger.log_exc(self.name)
58 logger.log('%s: recreating bad vserver' % rec['name'])
59 self.destroy(rec['name'])
60 self.create(rec['name'], rec['vref'])
61 vserver.VServer.__init__(self, rec['name'],logfile='/var/log/nm')
66 self.slice_id = rec['slice_id']
67 self.disk_usage_initialized = False
68 self.initscriptchanged = False
72 def create(name, vref = None):
73 logger.verbose('Sliver_VS:create - name=%s'%name)
77 ### locating the right slicefamily
78 # this is a first draft, and more a proof of concept thing
79 # the idea is to parse vref for dash-separated wishes,
80 # and to project these against the defaults
81 # so e.g. if the default slice family (as found in /etc/planetlab/slicefamily)
82 # is planetlab-f8-i386, then here is what we get
83 # vref=x86_64 -> vuseradd -t planetlab-f8-x86_64
84 # vref=centos5 -> vuseradd -t planetlab-centos5-i386
85 # vref=centos5-onelab -> vuseradd -t onelab-centos5-i386
86 # vref=planetflow -> vuseradd -t planetflow-f8-i386
87 # vref=x86_64-planetflow -> vuseradd -t planetflow-f8-x86_64
90 default=file("/etc/planetlab/slicefamily").read().strip()
91 (pldistro,fcdistro,arch) = default.split("-")
92 # from the slice attribute: cut dashes and try to figure the meaning
93 slice_wishes = vref.split("-")
94 for wish in slice_wishes:
95 if wish == "i386" or wish == "x86_64":
97 elif wish == "f8" or wish == "centos5" :
103 refname="-".join( (pldistro,fcdistro,arch) )
105 # check the templates exists -- there's probably a better way..
106 if not os.path.isdir ("/vservers/.vref/%s"%refname):
107 logger.verbose("%s (%s) : vref %s not found, using default %s"%(
108 name,vref,refname,default))
110 # could check again, but as we have /etc/slicefamily
111 # there's probably no /vservers/.vref/default
114 # have not found slicefamily
115 logger.verbose("%s (%s): legacy node - using fallback vrefname 'default'"%(name,vref))
120 logger.log("%s (%s) : unexpected error follows - using 'default'"%(
122 logger.log(traceback.format_exc())
125 logger.log_call('/usr/sbin/vuseradd', '-t', refname, name)
126 open('/vservers/%s/etc/slicename' % name, 'w').write(name)
129 def destroy(name): logger.log_call('/usr/sbin/vuserdel', name)
131 def configure(self, rec):
132 new_rspec = rec['_rspec']
133 if new_rspec != self.rspec:
134 self.rspec = new_rspec
137 new_initscript = rec['initscript']
138 if new_initscript != self.initscript:
139 self.initscript = new_initscript
140 logger.log('%s: installing initscript' % self.name)
141 def install_initscript():
142 flags = os.O_WRONLY | os.O_CREAT | os.O_TRUNC
143 fd = os.open('/etc/rc.vinit', flags, 0755)
144 os.write(fd, new_initscript)
147 self.chroot_call(install_initscript)
148 self.initscriptchanged = True
149 except: logger.log_exc(self.name)
151 accounts.Account.configure(self, rec) # install ssh keys
153 def start(self, delay=0):
154 if self.rspec['enabled'] > 0:
155 logger.log('%s: starting in %d seconds' % (self.name, delay))
157 # VServer.start calls fork() internally
158 vserver.VServer.start(self)
160 else: logger.log('%s: not starting, is not enabled' % self.name)
161 self.initscriptchanged = False
164 logger.log('%s: stopping' % self.name)
165 vserver.VServer.stop(self)
167 def set_resources(self):
168 disk_max = self.rspec['disk_max']
169 logger.log('%s: setting max disk usage to %d KiB' % (self.name, disk_max))
170 try: # if the sliver is over quota, .set_disk_limit will throw an exception
171 if not self.disk_usage_initialized:
172 self.vm_running = False
173 logger.log('%s: computing disk usage: beginning' % self.name)
174 Sliver_VS._init_disk_info_sem.acquire()
175 try: self.init_disk_info()
176 finally: Sliver_VS._init_disk_info_sem.release()
177 logger.log('%s: computing disk usage: ended' % self.name)
178 self.disk_usage_initialized = True
179 vserver.VServer.set_disklimit(self, max(disk_max, self.disk_blocks))
181 logger.log('%s: failed to set max disk usage' % self.name)
182 logger.log_exc(self.name)
184 # get/set the min/soft/hard values for all of the vserver
185 # related RLIMITS. Note that vserver currently only
186 # implements support for hard limits.
187 for limit in vserver.RLIMITS.keys():
189 minimum = self.rspec['%s_min'%type]
190 soft = self.rspec['%s_soft'%type]
191 hard = self.rspec['%s_hard'%type]
192 update = self.set_rlimit(limit, hard, soft, minimum)
194 logger.log('%s: setting rlimit %s to (%d, %d, %d)'
195 % (self.name, type, hard, soft, minimum))
197 self.set_capabilities_config(self.rspec['capabilities'])
198 if self.rspec['capabilities']:
199 logger.log('%s: setting capabilities to %s' % (self.name, self.rspec['capabilities']))
201 cpu_pct = self.rspec['cpu_pct']
202 cpu_share = self.rspec['cpu_share']
204 if self.rspec['enabled'] > 0:
206 logger.log('%s: setting cpu reservation to %d%%' % (self.name, cpu_pct))
211 logger.log('%s: setting cpu share to %d' % (self.name, cpu_share))
215 self.set_sched_config(cpu_pct, cpu_share)
216 # if IP address isn't set (even to 0.0.0.0), sliver won't be able to use network
217 if self.rspec['ip_addresses'] != '0.0.0.0':
218 logger.log('%s: setting IP address(es) to %s' % \
219 (self.name, self.rspec['ip_addresses']))
220 self.set_ipaddresses_config(self.rspec['ip_addresses'])
222 if self.is_running():
223 logger.log("%s: Setting name to %s" % (self.name, self.slice_id),2)
224 self.setname(self.slice_id)
226 if False: # Does not work properly yet.
227 if self.have_limits_changed():
228 logger.log('%s: limits have changed --- restarting' % self.name)
230 while self.is_running() and stopcount > 0:
234 stopcount = stopcount - 1
237 else: # tell vsh to disable remote login by setting CPULIMIT to 0
238 logger.log('%s: disabling remote login' % self.name)
239 self.set_sched_config(0, 0)