To look at the available probes, the probe-feature must first be enabled, which can be done with the enable-probes command. When the feature is enabled all probes in the system are detected and/or implicitly created. Also, any further creation or deletion of Simics objects is monitored, keeping the list of known probes in sync with the simulated system.
When the probes framework is enabled, a singleton object
called probes is created, which holds all commands to
examine probes. For example the probes.list command
gives an overview of the probes that is available in the system, and
the amount of objects for each probe name.
See figure 22 for some examples.
$> ./simics targets/qsp-x86/firststeps.simics num_cores=2 simics> enable-probes simics> probes.list ┌─────────┬──────────────────────────────────┬─────────────────────┬───┬──────────────────────────────────────────────┐ │ Row # │ Probe Name │ Display Name │Num│ Description │ ├─────────┼──────────────────────────────────┼─────────────────────┼───┼──────────────────────────────────────────────┤ │ 1│cell.cycles │Cycles │ 1│Total number of expired cycles in all │ │ │ │ │ │processors in a specific cell │ ├─────────┼──────────────────────────────────┼─────────────────────┼───┼──────────────────────────────────────────────┤ │ 2│cell.esteps │Esteps │ 1│Total number of executed steps (~instructions)│ │ │ │ │ │on all processors in a specific cell, │ │ │ │ │ │ignoring any halt steps │ ├─────────┼──────────────────────────────────┼─────────────────────┼───┼──────────────────────────────────────────────┤ │ 3│cell.exec_mode.hypersim_percent │HYP% │ 1│Percent of instructions executed in hypersim │ │ │ │ │ │mode in a specific cell │ ├─────────┼──────────────────────────────────┼─────────────────────┼───┼──────────────────────────────────────────────┤ │ 4│cell.exec_mode.hypersim_steps │Hypersim steps │ 1│Total number of instruction executed in │ │ │ │ │ │hypersim mode for all processors in a specific│ │ │ │ │ │cell │ ├─────────┼──────────────────────────────────┼─────────────────────┼───┼──────────────────────────────────────────────┤ ... simics> probes.list substr = cpu. -active ┌─────┬────────────────────────────┬─────────────────────┬───┬────────────────────────────────────────────────────┐ │Row #│ Probe Name │ Display Name │Num│ Description │ ├─────┼────────────────────────────┼─────────────────────┼───┼────────────────────────────────────────────────────┤ │ 1│cpu.cycles │Cycles │ 2│Number of cycles expired on this processor │ ├─────┼────────────────────────────┼─────────────────────┼───┼────────────────────────────────────────────────────┤ │ 2│cpu.disabled_reason │Disabled reason │ 2│Reports the current reason why a processor is not │ │ │ │ │ │running instructions (as a string) │ ├─────┼────────────────────────────┼─────────────────────┼───┼────────────────────────────────────────────────────┤ │ 3│cpu.esteps │Esteps │ 2│Number of executed steps (~instructions) on this │ │ │ │ │ │processor, ignoring any halt steps │ ├─────┼────────────────────────────┼─────────────────────┼───┼────────────────────────────────────────────────────┤ │ 4│cpu.exec_mode.hypersim_steps│Hypersim steps │ 2│Number of steps executed in hypersim execution mode.│ ├─────┼────────────────────────────┼─────────────────────┼───┼────────────────────────────────────────────────────┤ │ 5│cpu.picoseconds │picoseconds │ 2│Number of picoseconds expired on this processor │ ├─────┼────────────────────────────┼─────────────────────┼───┼────────────────────────────────────────────────────┤ │ 6│cpu.steps │Steps │ 2│Number of steps (~instructions) consumed by this │ │ │ │ │ │processor, including any halt steps │ ├─────┼────────────────────────────┼─────────────────────┼───┼────────────────────────────────────────────────────┤ │ 7│cpu.time.virtual │Virtual-Time │ 2│The virtual time of this 'cpu' │ ├─────┼────────────────────────────┼─────────────────────┼───┼────────────────────────────────────────────────────┤ │ 8│cpu.vmp.vmexits.histogram │vmp.vmexits.histogram│ 2│Histogram of vmexits │ ├─────┼────────────────────────────┼─────────────────────┼───┼────────────────────────────────────────────────────┤ │ 9│cpu.vmp.vmexits.total │vmp.vmexits.total │ 2│Total number of vmexits │ ├─────┼────────────────────────────┼─────────────────────┼───┼────────────────────────────────────────────────────┤ │ 10│cpu.vmp.vmrets.total │vmp.vmrets.total │ 2│Total number of vmrets │ ├─────┼────────────────────────────┼─────────────────────┼───┼────────────────────────────────────────────────────┤ │Sum │ │ │ 20│ │ └─────┴────────────────────────────┴─────────────────────┴───┴────────────────────────────────────────────────────┘ simics> probes.list -objects substr = cpu.steps ┌─────┬──────────┬────────────┬───┬────────────────────────────────────────┬─────────────────────────────────────────┐ │Row #│Probe Name│Display Name│Num│ Objects │ Description │ ├─────┼──────────┼────────────┼───┼────────────────────────────────────────┼─────────────────────────────────────────┤ │ 1│cpu.steps │Steps │ 2│board.mb.cpu0.core[0][0], board.mb.cpu0.│Number of steps (~instructions) consumed │ │ │ │ │ │core[1][0] │by this processor, including any halt │ │ │ │ │ │ │steps │ ├─────┼──────────┼────────────┼───┼────────────────────────────────────────┼─────────────────────────────────────────┤ │Sum │ │ │ 2│ │ │ └─────┴──────────┴────────────┴───┴────────────────────────────────────────┴─────────────────────────────────────────┘
The probes.list-details shows further information on each individual probe, including the different objects where the probes are located and their current values. See figure 23 for some examples.
simics> disable-vmp simics> run-seconds 1 simics> probes.list-details substr = cpu. -active ┌─────┬────────────────────────────┬───────────────────────────┬────────────────────────┬───────────────┐ │Row #│ Probe Name │ Categories │ Source Object │Formatted Value│ ├─────┼────────────────────────────┼───────────────────────────┼────────────────────────┼───────────────┤ │ 1│cpu.time.virtual │cpu time │board.mb.cpu0.core[0][0]│ 00:00:01.00│ │ 2│cpu.disabled_reason │cpu disabled │board.mb.cpu0.core[0][0]│ │ │ 3│cpu.esteps │cpu instructions steps │board.mb.cpu0.core[0][0]│ 588903799│ │ 4│cpu.exec_mode.hypersim_steps│hypersim performance steps │board.mb.cpu0.core[0][0]│ 163570386│ │ 5│cpu.steps │cpu instructions steps │board.mb.cpu0.core[0][0]│ 588903799│ │ 6│cpu.vmp.vmexits.total │vmp performance │board.mb.cpu0.core[0][0]│ 0│ │ 7│cpu.picoseconds │cpu cycles time picoseconds│board.mb.cpu0.core[0][0]│ 1000000000000│ │ 8│cpu.cycles │cpu cycles time │board.mb.cpu0.core[0][0]│ 2000000000│ │ 9│cpu.vmp.vmrets.total │vmp performance │board.mb.cpu0.core[0][0]│ 0│ │ 10│cpu.vmp.vmexits.histogram │vmp performance │board.mb.cpu0.core[0][0]│ │ │ 11│cpu.steps │cpu instructions steps │board.mb.cpu0.core[1][0]│ 193224419│ │ 12│cpu.esteps │cpu instructions steps │board.mb.cpu0.core[1][0]│ 193224419│ │ 13│cpu.vmp.vmrets.total │vmp performance │board.mb.cpu0.core[1][0]│ 0│ │ 14│cpu.picoseconds │cpu cycles time picoseconds│board.mb.cpu0.core[1][0]│ 1000000000000│ │ 15│cpu.cycles │cpu cycles time │board.mb.cpu0.core[1][0]│ 2000000000│ │ 16│cpu.time.virtual │cpu time │board.mb.cpu0.core[1][0]│ 00:00:01.00│ │ 17│cpu.disabled_reason │cpu disabled │board.mb.cpu0.core[1][0]│ HLT│ │ 18│cpu.exec_mode.hypersim_steps│hypersim performance steps │board.mb.cpu0.core[1][0]│ 192780981│ │ 19│cpu.vmp.vmexits.total │vmp performance │board.mb.cpu0.core[1][0]│ 0│ │ 20│cpu.vmp.vmexits.histogram │vmp performance │board.mb.cpu0.core[1][0]│ │ └─────┴────────────────────────────┴───────────────────────────┴────────────────────────┴───────────────┘ simics> probes.list-details categories = time -active ┌─────┬───────────────────┬───────────────────────────┬────────────────────────┬───────────────┐ │Row #│ Probe Name │ Categories │ Source Object │Formatted Value│ ├─────┼───────────────────┼───────────────────────────┼────────────────────────┼───────────────┤ │ 1│host.time.wallclock│host time │- │ 00:05:10.43│ │ 2│sim.time.virtual │time │- │ 00:00:01.00│ │ 3│cpu.time.virtual │cpu time │board.mb.cpu0.core[0][0]│ 00:00:01.00│ │ 4│cpu.picoseconds │cpu cycles time picoseconds│board.mb.cpu0.core[0][0]│ 1000000000000│ │ 5│cpu.cycles │cpu cycles time │board.mb.cpu0.core[0][0]│ 2000000000│ │ 6│cpu.picoseconds │cpu cycles time picoseconds│board.mb.cpu0.core[1][0]│ 1000000000000│ │ 7│cpu.cycles │cpu cycles time │board.mb.cpu0.core[1][0]│ 2000000000│ │ 8│cpu.time.virtual │cpu time │board.mb.cpu0.core[1][0]│ 00:00:01.00│ └─────┴───────────────────┴───────────────────────────┴────────────────────────┴───────────────┘
Some probes are not active by default, typically because there could be overhead in maintaining their values. To activate a probe the probes.subscribe can be used. As long as there are at least one subscriber on a probe, it will be active, and when the number of subscribers goes down to zero, the probe becomes deactivated again.
An individual probe can also be read out and used in a CLI script using the probes.read command. Figure 24 shows some examples where probes first need to be subscribed in order to be read later.
simics> probes.list-details categories = performance ┌───────┬──────────────────────────────────┬───────────────────────────────────────────────────┬────────────────────────┬───────────────┐ │ Row # │ Probe Name │ Categories │ Source Object │Formatted Value│ ├───────┼──────────────────────────────────┼───────────────────────────────────────────────────┼────────────────────────┼───────────────┤ │ 1│sim.module_profile │performance │- │ inactive│ │ 2│sim.vmp.vmexits.histogram │vmp performance │- │ inactive│ │ 3│sim.exec_mode.hypersim_steps │hypersim performance steps │- │ inactive│ │ 4│sim.exec_mode.interpreter_steps │interpreter performance steps │- │ inactive│ │ 5│sim.time.schedule │performance │- │ inactive│ │ 6│sim.exec_mode.interpreter_percent │performance instructions steps interpreter cpu │- │ inactive│ │ 7│sim.mips │steps host performance instructions cpu time │- │ inactive│ │ 8│sim.exec_mode.jit_steps │jit performance │- │ inactive│ │ 9│sim.exec_mode.vmp_steps │vmp performance steps │- │ inactive│ │ 10│sim.exec_mode.hypersim_percent │cpu hypersim performance instructions steps │- │ inactive│ │ 11│sim.exec_mode.vmp_percent │instructions vmp performance steps cpu │- │ inactive│ │ 12│sim.exec_mode.jit_percent │jit steps performance instructions cpu │- │ inactive│ │ 13│cell.exec_mode.hypersim_steps │hypersim performance steps │board.cell │ inactive│ │ 14│cell.exec_mode.interpreter_steps │interpreter performance steps │board.cell │ inactive│ │ 15│cell.vmp.vmexits.histogram │vmp performance │board.cell │ inactive│ │ 16│cell.exec_mode.jit_steps │jit performance │board.cell │ inactive│ │ 17│cell.mips │steps performance instructions cpu │board.cell │ inactive│ │ 18│cell.exec_mode.vmp_steps │vmp performance steps │board.cell │ inactive│ │ 19│cell.schedule_percent │cell performance instructions steps cpu │board.cell │ inactive│ │ 20│cell.exec_mode.hypersim_percent │cpu hypersim cell performance instructions steps │board.cell │ inactive│ │ 21│cell.exec_mode.interpreter_percent│cell performance instructions steps interpreter cpu│board.cell │ inactive│ │ 22│cell.exec_mode.jit_percent │jit cell performance instructions steps cpu │board.cell │ inactive│ │ 23│cell.exec_mode.vmp_percent │cell instructions vmp performance steps cpu │board.cell │ inactive│ │ 24│cpu.time.schedule │performance │board.mb.cpu0.core[0][0]│ inactive│ │ 25│cpu.exec_mode.interpreter_steps │interpreter performance steps │board.mb.cpu0.core[0][0]│ inactive│ │ 26│cpu.exec_mode.hypersim_steps │hypersim performance steps │board.mb.cpu0.core[0][0]│ 163570386│ │ 27│cpu.vmp.vmrets.total │vmp performance │board.mb.cpu0.core[0][0]│ 0│ │ 28│cpu.vmp.vmexits.histogram │vmp performance │board.mb.cpu0.core[0][0]│ │ │ 29│cpu.vmp.vmexits.total │vmp performance │board.mb.cpu0.core[0][0]│ 0│ │ 30│cpu.mips │steps performance instructions cpu │board.mb.cpu0.core[0][0]│ inactive│ ... simics> probes.subscribe probe = sim.mips simics> probes.subscribe probe = sim.module_profile simics> run-seconds 10 simics> probes.read sim.module_profile x86-intel64.so 94 45% x86-p4e JIT 32 15% libsimics-common.so 19 9% libc.so.6 16 8% ICH10.so 8 4% libwx_gtk2u_core-3.0.so.0.4.0 8 4% libX11.so.6.4.0 6 3% libpython3.7m.so.1.0 5 2% x86_tlb.so 4 2% libvtutils.so 4 2% X58-devices.so 3 1% _core.cpython-37m-x86_64-linux-gnu.so 3 1% pcie-downstream-port.so 2 1% siplib.cpython-37m-x86_64-linux-gnu.so 1 0% libgdk-x11-2.0.so.0.2400.33 1 0% libwx_baseu-3.0.so.0.4.0 1 0% simics> probes.read sim.mips 1447864673.0263705 simics> probes.read sim.mips -formatted 1.45 G simics> probes.read sim.mips -raw-value 1.86e+09 / 1.28e+00 = 1.45e+09 (1447864673.03) simics> $p = (probes.read sim.mips) simics> echo $p 1447864673.0263705 simics> $p = (probes.read sim.mips -raw-value) simics> echo $p [1856871575, 1.282489730976522]
Without any formatting switches to read command, the calculated value of the probe is returned so it can be used in CLI scripts doing additional calculations.
The -formatted flag formats the value according to the
probe's properties. The -raw-value flag returns internal
representation of advanced types. This can be useful for understanding
the source-values for a calculated value.