def printParms(fmt, disk, raid, rados, site, multi):
"""
print out the parameters associated with a test
"""
if disk is not None:
print "Disk Modeling Parameters"
print " size: %10s" % printSize(disk.size)
print(" FIT rate: %10d (MTBF = %s)" %
(disk.fits, printTime(mttf(disk.fits))))
print " NRE rate: %10.1E" % disk.nre
if raid is not None:
print "RAID parameters"
print " replace: %16s" % printTime(raid.delay)
if raid.speed > 0:
print(" recovery rate: %7s/s (%s)" %
(printSize(raid.speed),
printTime(raid.rebuild_time())))
print " NRE model: %10s" % raid.nre_model
print " object size: %10s" % printSize(raid.objsize)
if rados is not None:
print "RADOS parameters"
print " auto mark-out: %14s" % printTime(rados.delay)
print(" recovery rate: %8s/s (%s/drive)" %
(printSize(rados.speed),
printTime(rados.rebuild_time(rados.speed))))
print " osd fullness: %7d%%" % (rados.full * 100)
print " declustering: %7d PG/OSD" % rados.pgs
print " NRE model: %10s" % rados.nre_model
print " object size: %7s" % \
printSize(rados.objsize, unit=1024)
print " stripe length:%7d" % rados.stripe
if site is not None:
print "Site parameters"
s = 0 if multi is None else multi.sites
if site.fits == 0:
print " disasters: IGNORED"
else:
tf = mttf(site.fits)
print(" disaster rate: %12s (%d FITS)" %
(printTime(tf), site.fits))
if site.replace == 0:
print " site recovery: NEVER"
else:
print " site recovery: %11s" % printTime(site.replace)
if multi is not None:
print(" recovery rate: %8s/s (%s/PG)" %
(printSize(multi.speed),
printTime(multi.rados.rebuild_time(multi.speed))))
if multi.latency == 0:
print " replication: synchronous"
else:
print(" replication: asynchronous (%s delay)" %
(fmt.printTime(multi.latency)))
def run(models, columns="", verbosity="default",
capacity=1*PiB, period=1*YEAR):
""" execute a single model and print out the results
models -- list of models to be run
columns -- what optional columns to include
verbosity -- what kind of output we want
capacity -- total system capacity (bytes)
period -- modeled time period (hours)
"""
# figure out what optional fields to include
showTr = False # FIX get from columns
showBW = False # FIX get from columns
# define the column headings
heads = [
"configuration", "<p,s>/PiB", "durability", "Ploss"
]
legends = [
"configuration being modeled",
"<primaries, secondaries> per petabyte",
"probability of object survival*",
"probability of loss*",
]
# consider the optional fields
if showBW:
heads.append("BW(recov)")
legends.append("peak recovery bandwidth")
if showTr:
heads.append("T(recov)")
legends.append("max detect/recovery time")
# figure out the longest description
maxlen = len(heads[0])
for m in models:
l = len(m.descr)
if l > maxlen:
maxlen = l
format = ColumnPrint(heads, maxdesc=maxlen)
# figure out what output he wants
parm1 = True # basic parameters at front
descr = True # descriptions of columns
headings = True # column headings
parms = True # all parameters for every model
debug = False # diagnostic output
if verbosity == "parameters": # per-test parameters
parm1 = False
descr = False
elif verbosity == "headings": # output and headings
parm1 = False
parms = False
descr = False
elif verbosity == "data": # minimal - just the output
parm1 = False
parms = False
descr = False
headings = False
elif verbosity == "all": # pretty much everyting
debug = True
parm1 = False
elif verbosity == "debug": # debug only
debug = True
headings = False
parm1 = False
parms = False
descr = False
else:
parms = False
# print out basic parameters (assumed not to change)
if parm1:
printParms(models[0], None, None)
# print out column legends
if descr:
print ""
print "Column legends:"
s = printTime(period)
i = 1
while i <= len(legends):
l = legends[i - 1]
if l.endswith('*'):
print "\t%d %s (per %s)" % (i, l, s)
else:
print "\t%d %s" % (i, l)
i += 1
# print out column headings
if headings:
format.printHeadings()
for m in models:
# compute sizes and rates
sizes = Sizes(m, capacity, debug)
rates = Rates(m, debug)
# print out the model parameters
if parms:
printParms(m, sizes, rates)
# compute and print the reliability
results = Results(m, sizes, rates, period, debug)
s = list()
s.append(m.descr)
if m.symmetric:
s.append("<%d>" % (sizes.n_primary))
else:
s.append("<%d,%d>" % (sizes.n_primary, sizes.n_secondary))
s.append(printDurability(results.durability))
s.append(printProbability(results.p_loss))
bw = max(results.bw_sfail, results.bw_pfail)
if showBW:
s.append("n/a" if bw == 0 else printSize(bw, 1000) + "/s")
if showTr:
s.append("n/a" if bw == 0 else printFloat(results.Trecov)+"s")
format.printLine(s)
def Run(tests, period=YEAR, verbosity="all"):
""" run and report a set of specified simulations
tests -- actual list of simulations to run
(print a header line for each None test)
period -- simulation period
verbosity -- output options
"""
# column headings
heads = ("storage", "durability",
"PL(site)", "PL(copies)", "PL(NRE)", "PL(rep)", "loss/PiB")
# column descriptions
legends = [
"storage unit/configuration being modeled",
"probability of object survival*",
"probability of loss due to site failures*",
"probability of loss due to drive failures*",
"probability of loss due to NREs during recovery*",
"probability of loss due to replication failure*",
"expected data loss per Petabyte*"
]
# use the headings to generate a format
format = ColumnPrint(heads, maxdesc=20)
# figure out what output he wants
headings = True
parms = True
descr = True
if verbosity == "parameters":
descr = False
elif verbosity == "headings":
parms = False
descr = False
elif verbosity == "data only":
parms = False
descr = False
headings = False
# introspect the tests to find the disk/raid/rados parameters
disk = None
raid = None
rados = None
site = None
multi = None
for t in tests:
c = t.__class__.__name__
if disk is None and "Disk" in c:
disk = t
if raid is None and c.startswith("RAID"):
raid = t
if rados is None and c.startswith("RADOS"):
rados = t
if site is None and c.startswith("Site"):
site = t
if multi is None and c.startswith("MultiSite"):
multi = t
# find elements that only exist beneath others
if site is None and multi is not None:
site = multi.site
if rados is None and multi is not None:
rados = multi.rados
if disk is None and rados is not None:
disk = rados.disk
if disk is None and raid is not None:
disk = raid.disk
if parms:
printParms(format, disk, raid, rados, site, multi)
if descr:
print ""
print "Column legends"
s = printTime(period)
i = 1
while i <= len(legends):
l = legends[i - 1]
if l.endswith('*'):
print "\t%d %s (per %s)" % (i, l, s)
else:
print "\t%d %s" % (i, l)
i += 1
if headings:
format.printHeadings()
# expected data loss after drive failures
for t in tests:
if t is None:
format.printHeadings()
continue
# calculate the renderable reliabilities and durability
s = list()
t.compute(period=period)
s.append(t.description) # description
s.append(printDurability(t.dur)) # durability
s.append(printProbability(t.P_site)) # P(site failure)
s.append(printProbability(t.P_drive)) # P(drive failure)
s.append(printProbability(t.P_nre)) # P(NRE on recovery)
s.append(printProbability(t.P_rep)) # P(replication failure)
l = (t.P_site * t.L_site) + (t.P_drive * t.L_drive) +\
(t.P_nre * t.L_nre) + (t.P_rep * t.L_rep)
s.append(printExp(l * PiB / t.rawsize)) # expected loss/PiB
format.printLine(s)
