TRAPSTAT(1M)TRAPSTAT(1M)NAMEtrapstat - report trap statistics
SYNOPSIS
/usr/sbin/trapstat [-t | -T | -e entry]
[-C processor_set_id | -c cpulist] [-P] [-a]
[-r rate] [ [interval [count]] | command | [args]]
/usr/sbin/trapstat -l
DESCRIPTION
The trapstat utility gathers and displays run-time trap statistics on
UltraSPARC-based systems. The default output is a table of trap types
and CPU IDs, with each row of the table denoting a trap type and each
column of the table denoting a CPU. If standard output is a terminal,
the table contains as many columns of data as can fit within the termi‐
nal width; if standard output is not a terminal, the table contains at
most six columns of data. By default, data is gathered and and dis‐
played for all CPUs; if the data cannot fit in a single table, it is
printed across multiple tables. The set of CPUs for which data is gath‐
ered and displayed can be optionally specified with the -c or -C
option.
Unless the -r option or the -a option is specified, the value displayed
in each entry of the table corresponds to the number of traps per sec‐
ond. If the -r option is specified, the value corresponds to the number
of traps over the interval implied by the specified sampling rate; if
the -a option is specified, the value corresponds to the accumulated
number of traps since the invocation of trapstat.
By default, trapstat displays data once per second, and runs indefi‐
nitely; both of these behaviors can be optionally controlled with the
interval and count parameters, respectively. The interval is specified
in seconds; the count indicates the number of intervals to be executed
before exiting. Alternatively, command can be specified, in which case
trapstat executes the provided command and continues to run until the
command exits. A positive integer is assumed to be an interval; if the
desired command cannot be distinguished from an integer, the full path
of command must be specified.
UltraSPARC I (obsolete), II, and III handle translation lookaside buf‐
fer (TLB) misses by trapping to the operating system. TLB miss traps
can be a significant component of overall system performance for some
workloads; the -t option provides in-depth information on these traps.
When run with this option, trapstat displays both the rate of TLB miss
traps and the percentage of time spent processing those traps. Addi‐
tionally, TLB misses that hit in the translation storage buffer (TSB)
are differentiated from TLB misses that further miss in the TSB. (The
TSB is a software structure used as a translation entry cache to allow
the TLB to be quickly filled; it is discussed in detail in the Ultra‐
SPARC II User's Manual.) The TLB and TSB miss information is further
broken down into user- and kernel-mode misses.
Workloads with working sets that exceed the TLB reach may spend a sig‐
nificant amount of time missing in the TLB. To accommodate such work‐
loads, the operating system supports multiple page sizes: larger page
sizes increase the effective TLB reach and thereby reduce the number of
TLB misses. To provide insight into the relationship between page size
and TLB miss rate, trapstat optionally provides in-depth TLB miss
information broken down by page size using the -T option. The informa‐
tion provided by the -T option is a superset of that provided by the -t
option; only one of -t and -T can be specified.
OPTIONS
The following options are supported:
-a
Displays the number of traps as accumulating,
monotonically increasing values instead of per-
second or per-interval rates.
-c cpulist
Enables trapstat only on the CPUs specified by
cpulist.
cpulist can be a single processor ID (for exam‐
ple, 4), a range of processor IDs (for example,
4-6), or a comma separated list of processor
IDs or processor ID ranges (for example, 4,5,6
or 4,6-8).
-C processor_set_id
Enables trapstat only on the CPUs in the pro‐
cessor set specified by processor_set_id.
trapstat modifies its output to always reflect
the CPUs in the specified processor set. If a
CPU is added to the set, trapstat modifies its
output to include the added CPU; if a CPU is
removed from the set, trapstat modifies its
output to exclude the removed CPU. At most one
processor set can be specified.
-e entrylist
Enables trapstat only for the trap table entry
or entries specified by entrylist. A trap table
entry can be specified by trap number or by
trap name (for example, the level-10 trap can
be specified as 74, 0x4A, 0x4a, or level-10).
entrylist can be a single trap table entry or a
comma separated list of trap table entries. If
the specified trap table entry is not valid,
trapstat prints a table of all valid trap table
entries and values. A list of valid trap table
entries is also found in The SPARC Architecture
Manual, Version 9 and the Sun Microelectronics
UltraSPARC II User's Manual. If the parsable
option (-P) is specified in addition to the -e
option, the format of the data is as follows:
Field Contents
1 Timestamp (nanoseconds since start)
2 CPU ID
3 Trap number (in hexadecimal)
4 Trap name
5 Trap rate per interval
Each field is separated with whitespace. If the
format is modified, it will be modified by
adding potentially new fields beginning with
field 6; exant fields will remain unchanged.
-l
Lists trap table entries. By default, a table
is displayed containing all valid trap numbers,
their names and a brief description. The trap
name is used in both the default output and in
the entrylist parameter for the -e argument. If
the parsable option (-P) is specified in addi‐
tion to the -l option, the format of the data
is as follows:
Field Contents
1 Trap number in hexadecimal
2 Trap number in decimal
3 Trap name
Remaining Trap description
-P
Generates parsable output. When run without
other data gathering modifying options (that
is, -e, -t or -T), trapstat's the parsable out‐
put has the following format:
Field Contents
1 Timestamp (nanoseconds since start)
2 CPU ID
3 Trap number (in hexadecimal)
4 Trap name
5 Trap rate per interval
Each field is separated with whitespace. If the
format is modified, it will be modified by
adding potentially new fields beginning with
field 6; extant fields will remain unchanged.
-r rate
Explicitly sets the sampling rate to be rate
samples per second. If this option is speci‐
fied, trapstat's output changes from a traps-
per-second to traps-per-sampling-interval.
-t
Enables TLB statistics.
A table is displayed with four principal col‐
umns of data: itlb-miss, itsb-miss, dtlb-miss,
and dtsb-miss. The columns contain both the
rate of the corresponding event and the per‐
centage of CPU time spent processing the event.
The percentage of CPU time is given only in
terms of a single CPU. The rows of the table
correspond to CPUs, with each CPU consuming two
rows: one row for user-mode events (denoted
with u) and one row for kernel-mode events
(denoted with k). For each row, the percentage
of CPU time is totalled and displayed in the
rightmost column. The CPUs are delineated with
a solid line. If the parsable option (-P) is
specified in addition to the -t option, the
format of the data is as follows:
Field Contents
1 Timestamp (nanoseconds since start)
2 CPU ID
3 Mode (k denotes kernel, u denotes user)
4 I-TLB misses
5 Percentage of time in I-TLB miss handler
6 I-TSB misses
7 Percentage of time in I-TSB miss handler
8 D-TLB misses
9 Percentage of time in D-TLB miss handler
10 D-TSB misses
11 Percentage of time in D-TSB miss handler
Each field is separated with whitespace. If the
format is modified, it will be modified by
adding potentially new fields beginning with
field 12; extant fields will remain unchanged.
-T
Enables TLB statistics, with page size informa‐
tion. As with the -t option, a table is dis‐
played with four principal columns of data:
itlb-miss, itsb-miss, dtlb-miss, and dtsb-miss.
The columns contain both the absolute number of
the corresponding event, and the percentage of
CPU time spent processing the event. The per‐
centage of CPU time is given only in terms of a
single CPU. The rows of the table correspond to
CPUs, with each CPU consuming two sets of rows:
one set for user-level events (denoted with u)
and one set for kernel-level events (denoted
with k). Each set, in turn, contains as many
rows as there are page sizes supported (see
getpagesizes(3C)). For each row, the percentage
of CPU time is totalled and displayed in the
right-most column. The two sets are delineated
with a dashed line; CPUs are delineated with a
solid line. If the parsable option (-P) is
specified in addition to the -T option, the
format of the data is as follows:
Field Contents
1 Timestamp (nanoseconds since start)
2 CPU ID
3 Mode k denotes kernel, u denotes user)
4 Page size, in decimal
5 I-TLB misses
6 Percentage of time in I-TLB miss handler
7 I-TSB misses
8 Percentage of time in I-TSB miss handler
9 D-TLB misses
10 Percentage of time in D-TLB miss handler
11 D-TSB misses
12 Percentage of time in D-TSB miss handler
Each field is separated with whitespace. If the
format is modified, it will be modified by
adding potentially new fields beginning with
field 13; extant fields will remain unchanged.
EXAMPLES
Example 1 Using trapstat Without Options
When run without options, trapstat displays a table of trap types and
CPUs. At most six columns can fit in the default terminal width; if (as
in this example) there are more than six CPUs, multiple tables are dis‐
played:
example# trapstat
vct name | cpu0 cpu1 cpu4 cpu5 cpu8 cpu9
------------------------+------------------------------------------------------
24 cleanwin | 6446 4837 6368 2153 2623 1321
41 level-1 | 100 0 0 0 1 0
44 level-4 | 0 1 1 1 0 0
45 level-5 | 0 0 0 0 0 0
47 level-7 | 0 0 0 0 9 0
49 level-9 | 100 100 100 100 100 100
4a level-10 | 100 0 0 0 0 0
4d level-13 | 6 10 7 16 13 11
4e level-14 | 100 0 0 0 1 0
60 int-vec | 2607 2740 2642 2922 2920 3033
64 itlb-miss | 3129 2475 3167 1037 1200 569
68 dtlb-miss | 121061 86162 109838 37386 45639 20269
6c dtlb-prot | 997 847 1061 379 406 184
84 spill-user-32 | 2809 2133 2739 200806 332776 454504
88 spill-user-64 | 45819 207856 93487 228529 68373 77590
8c spill-user-32-cln | 784 561 767 274 353 215
90 spill-user-64-cln | 9 37 17 39 12 13
98 spill-kern-64 | 62913 50145 63869 21916 28431 11738
a4 spill-asuser-32 | 1327 947 1288 460 572 335
a8 spill-asuser-64 | 26 48 18 54 10 14
ac spill-asuser-32-cln | 4580 3599 4555 1538 1978 857
b0 spill-asuser-64-cln | 26 0 0 2 0 0
c4 fill-user-32 | 2862 2161 2798 191746 318115 435850
c8 fill-user-64 | 45813 197781 89179 217668 63905 74281
cc fill-user-32-cln | 3802 2833 3733 10153 16419 19475
d0 fill-user-64-cln | 329 10105 4873 10603 4235 3649
d8 fill-kern-64 | 62519 49943 63611 21824 28328 11693
108 syscall-32 | 2285 1634 2278 737 957 383
126 self-xcall | 100 0 0 0 0 0
vct name | cpu12 cpu13 cpu14 cpu15
------------------------+------------------------------------
24 cleanwin | 5435 4232 6302 6104
41 level-1 | 0 0 0 0
44 level-4 | 2 0 0 1
45 level-5 | 0 0 0 0
47 level-7 | 0 0 0 0
49 level-9 | 100 100 100 100
4a level-10 | 0 0 0 0
4d level-13 | 15 11 22 11
4e level-14 | 0 0 0 0
60 int-vec | 2813 2833 2738 2714
64 itlb-miss | 2636 1925 3133 3029
68 dtlb-miss | 90528 70639 107786 103425
6c dtlb-prot | 819 675 988 954
84 spill-user-32 | 175768 39933 2811 2742
88 spill-user-64 | 0 241348 96907 118298
8c spill-user-32-cln | 681 513 753 730
90 spill-user-64-cln | 0 42 16 20
98 spill-kern-64 | 52158 40914 62305 60141
a4 spill-asuser-32 | 1113 856 1251 1208
a8 spill-asuser-64 | 0 64 16 24
ac spill-asuser-32-cln | 3816 2942 4515 4381
b0 spill-asuser-64-cln | 0 0 0 0
c4 fill-user-32 | 170744 38444 2876 2784
c8 fill-user-64 | 0 230381 92941 111694
cc fill-user-32-cln | 8550 3790 3612 3553
d0 fill-user-64-cln | 0 10726 4495 5845
d8 fill-kern-64 | 51968 40760 62053 59922
108 syscall-32 | 1839 1495 2144 2083
126 self-xcall | 0 0 0 0
Example 2 Using trapset with CPU Filtering
The -c option can be used to limit the CPUs on which trapstat is
enabled. This example limits CPU 1 and CPUs 12 through 15.
example# trapstat-c 1,12-15
vct name | cpu1 cpu12 cpu13 cpu14 cpu15
------------------------+---------------------------------------------
24 cleanwin | 6923 3072 2500 3518 2261
44 level-4 | 3 0 0 1 1
49 level-9 | 100 100 100 100 100
4d level-13 | 23 8 14 19 14
60 int-vec | 2559 2699 2752 2688 2792
64 itlb-miss | 3296 1548 1174 1698 1087
68 dtlb-miss | 114788 54313 43040 58336 38057
6c dtlb-prot | 1046 549 417 545 370
84 spill-user-32 | 66551 29480 301588 26522 213032
88 spill-user-64 | 0 318652 111239 299829 221716
8c spill-user-32-cln | 856 347 331 416 293
90 spill-user-64-cln | 0 55 21 59 39
98 spill-kern-64 | 66464 31803 24758 34004 22277
a4 spill-asuser-32 | 1423 569 560 698 483
a8 spill-asuser-64 | 0 74 32 98 46
ac spill-asuser-32-cln | 4875 2250 1728 2384 1584
b0 spill-asuser-64-cln | 0 2 0 1 0
c4 fill-user-32 | 64193 28418 287516 27055 202093
c8 fill-user-64 | 0 305016 106692 288542 210654
cc fill-user-32-cln | 6733 3520 15185 2396 12035
d0 fill-user-64-cln | 0 13226 3506 12933 11032
d8 fill-kern-64 | 66220 31680 24674 33892 22196
108 syscall-32 | 2446 967 817 1196 755
Example 3 Using trapstat with TLB Statistics
The -t option displays in-depth TLB statistics, including the amount of
time spent performing TLB miss processing. The following example shows
that the machine is spending 14.1 percent of its time just handling D-
TLB misses:
example# trapstat-t
cpu m| itlb-miss %tim itsb-miss %tim | dtlb-miss %tim dtsb-miss %tim |%tim
-----+-------------------------------+-------------------------------+----
0 u| 2571 0.3 0 0.0 | 10802 1.3 0 0.0 | 1.6
0 k| 0 0.0 0 0.0 | 106420 13.4 184 0.1 |13.6
-----+-------------------------------+-------------------------------+----
1 u| 3069 0.3 0 0.0 | 10983 1.2 100 0.0 | 1.6
1 k| 27 0.0 0 0.0 | 106974 12.6 19 0.0 |12.7
-----+-------------------------------+-------------------------------+----
2 u| 3033 0.3 0 0.0 | 11045 1.2 105 0.0 | 1.6
2 k| 43 0.0 0 0.0 | 107842 12.7 108 0.0 |12.8
-----+-------------------------------+-------------------------------+----
3 u| 2924 0.3 0 0.0 | 10380 1.2 121 0.0 | 1.6
3 k| 54 0.0 0 0.0 | 102682 12.2 16 0.0 |12.2
-----+-------------------------------+-------------------------------+----
4 u| 3064 0.3 0 0.0 | 10832 1.2 120 0.0 | 1.6
4 k| 31 0.0 0 0.0 | 107977 13.0 236 0.1 |13.1
=====+===============================+===============================+====
ttl | 14816 0.3 0 0.0 | 585937 14.1 1009 0.0 |14.5
Example 4 Using trapstat with TLB Statistics and Page Size Information
By specifying the -T option, trapstat shows TLB misses broken down by
page size. In this example, CPU 0 is spending 7.9 percent of its time
handling user-mode TLB misses on 8K pages, and another 2.3 percent of
its time handling user-mode TLB misses on 64K pages.
example# trapstat-T -c 0
cpu m size| itlb-miss %tim itsb-miss %tim | dtlb-miss %tim dtsb-miss %tim |%tim
----------+-------------------------------+-------------------------------+----
0 u 8k| 1300 0.1 15 0.0 | 104897 7.9 90 0.0 | 8.0
0 u 64k| 0 0.0 0 0.0 | 29935 2.3 7 0.0 | 2.3
0 u 512k| 0 0.0 0 0.0 | 3569 0.2 2 0.0 | 0.2
0 u 4m| 0 0.0 0 0.0 | 233 0.0 2 0.0 | 0.0
- - - - - + - - - - - - - - - - - - - - - + - - - - - - - - - - - - - - - + - -
0 k 8k| 13 0.0 0 0.0 | 71733 6.5 110 0.0 | 6.5
0 k 64k| 0 0.0 0 0.0 | 0 0.0 0 0.0 | 0.0
0 k 512k| 0 0.0 0 0.0 | 0 0.0 206 0.1 | 0.1
0 k 4m| 0 0.0 0 0.0 | 0 0.0 0 0.0 | 0.0
==========+===============================+===============================+====
ttl | 1313 0.1 15 0.0 | 210367 17.1 417 0.2 |17.5
Example 5 Using trapstat with Entry Filtering
By specifying the -e option, trapstat displays statistics for only spe‐
cific trap types. Using this option minimizes the probe effect when
seeking specific data. This example yields statistics for only the
dtlb-prot and syscall-32 traps on CPUs 12 through 15:
example# trapstat-e dtlb-prot,syscall-32 -c 12-15
vct name | cpu12 cpu13 cpu14 cpu15
------------------------+------------------------------------
6c dtlb-prot | 817 754 1018 560
108 syscall-32 | 1426 1647 2186 1142
vct name | cpu12 cpu13 cpu14 cpu15
------------------------+------------------------------------
6c dtlb-prot | 1085 996 800 707
108 syscall-32 | 2578 2167 1638 1452
Example 6 Using trapstat with a Higher Sampling Rate
The following example uses the -r option to specify a sampling rate of
1000 samples per second, and filter only for the level-10 trap. Addi‐
tionally, specifying the -P option yields parsable output.
Notice the timestamp difference between the level-10 events: 9,998,000
nanoseconds and 10,007,000 nanoseconds. These level-10 events corre‐
spond to the system clock, which by default ticks at 100 hertz (that
is, every 10,000,000 nanoseconds).
example# trapstat-e level-10 -P -r 1000
1070400 0 4a level-10 0
2048600 0 4a level-10 0
3030400 0 4a level-10 1
4035800 0 4a level-10 0
5027200 0 4a level-10 0
6027200 0 4a level-10 0
7027400 0 4a level-10 0
8028200 0 4a level-10 0
9026400 0 4a level-10 0
10029600 0 4a level-10 0
11028600 0 4a level-10 0
12024000 0 4a level-10 0
13028400 0 4a level-10 1
14031200 0 4a level-10 0
15027200 0 4a level-10 0
16027600 0 4a level-10 0
17025000 0 4a level-10 0
18026000 0 4a level-10 0
19027800 0 4a level-10 0
20025600 0 4a level-10 0
21025200 0 4a level-10 0
22025000 0 4a level-10 0
23035400 0 4a level-10 1
24027400 0 4a level-10 0
25026000 0 4a level-10 0
26027000 0 4a level-10 0
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌────────────────────────────────────────────┐
│ ATTRIBUTE TYPE ATTRIBUTE VALUE │
│Interface Stability │
│ Human Readable Output Unstable │
│ Parsable Output Evolving │
└────────────────────────────────────────────┘
SEE ALSOlockstat(1M), pmap(1), psrset(1M), psrinfo(1M), pbind(1M), ppgsz(1),
getpagesizes(3C)
Sun Microelectronics UltraSPARC II User's Manual, January 1997,
STP1031,
The SPARC Architecture Manual, Version 9, 1994, Prentice-Hall.
NOTES
When enabled, trapstat induces a varying probe effect, depending on the
type of information collected. While the precise probe effect depends
upon the specifics of the hardware, the following table can be used as
a rough guide:
Option Approximate probe effect
default 3-5% per trap
-e 3-5% per specified trap
-t, -T 40-45% per TLB miss trap
hitting in the TSB, 25-30%
per TLB miss trap missing
in the TSB
These probe effects are per trap not for the system as a whole. For
example, running trapstat with the default options on a system that
spends 7% of total time handling traps induces a performance degrada‐
tion of less than one half of one percent; running trapstat with the -t
or -T option on a system spending 5% of total time processing TLB
misses induce a performance degradation of no more than 2.5%.
When run with the -t or -T option, trapstat accounts for its probe
effect when calculating the %tim fields. This assures that the %tim
fields are a reasonably accurate indicator of the time a given workload
is spending handling TLB misses — regardless of the perturbing presence
of trapstat.
While the %tim fields include the explicit cost of executing the TLB
miss handler, they do not include the implicit costs of TLB miss traps
(for example, pipeline effects, cache pollution, etc). These implicit
costs become more significant as the trap rate grows; if high %tim val‐
ues are reported (greater than 50%), you can accurately infer that much
of the balance of time is being spent on the implicit costs of the TLB
miss traps.
Due to the potential system wide degradation induced, only the super-
user can run trapstat.
Due to the limitation of the underlying statistics gathering methodol‐
ogy, only one instance of trapstat can run at a time.
May 11, 2004 TRAPSTAT(1M)
