A recent commit eliminated the potential for a storage
violation with forest view mode. It occurred when some
program (erroneously?) created a lengthy forking loop.
However, the associated commit message was misleading.
The message implied that an unexpected order following
a sort on start_time was the cause of storage overruns
and a 'char' used to track nesting level only distorts
the display when it goes negative. Actually, the truth
is really just the opposite. Any start_time sort quirk
causes no harm while that 'char' can yield corruption.
Should some child end up sorted ahead of its parent by
way of an extremely unlikely shared start_time the end
result is such a child will be displayed unnested just
like init or kthreadd along with all its own children.
However, if nesting levels exceeded 255 (and became 0)
a massive array overrun could be triggered when such a
task and *all* its children were added to an array for
the second time. Exactly how much storage was violated
depended on the number of children that zeroed process
had spawned (hinted at via either SIGSEGV or SIGABRT).
The earlier commit limited nested levels to 100 so the
root cause of the storage violation was already fixed.
The potential for distorted nesting levels due to sort
on start_time would seem to remain. But it's extremely
unlikely that 2 tasks would share the same start_time.
Even so, a new #define has been introduced which makes
top impervious to the order of tasks such that a qsort
is no longer necessary (providing an init/systemd task
exists & was harvested as the first task by readproc).
It can be utilized if distorted nesting ever becomes a
real issue. But since there is a 5-10% performance hit
with that, we'll continue using start_time as default.
References(s):
commit ce70017eb1
Signed-off-by: Jim Warner <james.warner@comcast.net>
This commit will eliminate a very nasty bug associated
with top's forest view mode. It addresses a potential
SIGSEGV/SIGABRT that was only encountered when another
program (erroneously?) creates a lengthy forking loop.
If the growing list of nested children is sufficiently
fast such that proc_t start_time is duplicated between
children then the sort upon which top relies might not
produce the expected order. That, in turn, could cause
the forest_adds function to initially miss some child.
But that missed child would be caught by forest_create
and eventually would cause our array boundary overrun.
Such overrun occurs when some child of that originally
*missed* child is found and a duplicate add attempted.
In correcting this bug we'll also use this opportunity
to prohibit a borrowed proc_t padding byte (char) from
going negative. If the nesting level exceeded 127, the
effect was an "unnesting" with the snprintf width then
viewed as flag+width also yielding left justification.
Henceforth, we'll limit nesting to 100 with subsequent
children shown as " + ", not the usual " `- " prefix.
References(s):
https://bugzilla.redhat.com/show_bug.cgi?id=1153642http://www.freelists.org/post/procps/Bug-in-the-forrest-view,6
Signed-off-by: Jim Warner <james.warner@comcast.net>
When startup defaults were changed users with existing
rcfiles would likely find their previous configuration
was not being honored in all respects. The disparities
involved Graphs modes and Summary/Task memory scaling.
This patch simply restores what was always intended as
the proper behavior for previously saved config files.
References(s):
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=762928https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=762947
. new startup defaults
commit 8ef6cd91fc
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch will cure a potential aberration associated
with a terminal's size (SIGWINCH) and top's new graphs
modes. The symptoms were a dangling tilde (~) plus the
potential loss of a graph's right-most visual content.
The condition was only apparent when a %Cpu approached
100% usage. Also the apparent loss of content affected
the 'block' graph only. With 'bar' graphs, that affect
became the loss of proper right-most bar graph colors.
The cause was determined to be a combination of: 1) an
unnecessary snprintf precision specification; and 2) a
rounding quirk for any graphs which displayed distinct
types of information (as for user/syst, used/unavail).
These could then combine to produce an extra bar/block
which, in turn, resulted in the truncation of a pseudo
termcap attribute used by the show_special() function.
What was originally interpreted as an intractable race
condition turns out to be just a self inflicted wound.
Reference(s):
http://www.freelists.org/post/procps/top-Possible-bug-in-the-graphs,1
Signed-off-by: Jim Warner <james.warner@comcast.net>
Let's not report zero for kb_main_available when older
kernels don't have MemAvailable. Instead, if we simply
duplicate the 'free' amount we can avoid all ancillary
problems, such as those involving top's graphing mode.
Reference(s):
http://www.freelists.org/post/procps/kb-main-available-etc,3
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch will trade a former pessimistic calculation
of free physical memory for a more optimistic one that
uses the newly added kb_main_available library export.
But in case one might wish to return to the old former
method, there's a new #define that was made available.
[ the new calculation will affect graphing mode only ]
Reference(s):
http://www.freelists.org/post/procps/systemd-support-to-library,9
Signed-off-by: Jim Warner <james.warner@comcast.net>
Might as well use the newly exposed sysinfo.h variable
'page_bytes' rather than our own. Plus, in the process
we can avoid incurring yet one more function call hit.
Signed-off-by: Jim Warner <james.warner@comcast.net>
Gosh, just because most of us might run with some swap
file allocated, not every system might. I only wish my
testing methodology was as sophisticated as Jaromir's.
Reference(s):
http://www.freelists.org/post/procps/latest-top-enhancements,7
Signed-off-by: Jim Warner <james.warner@comcast.net>
Wow, even the linux/Documentation/filesystems/proc.txt
document doesn't provide us with that level of detail.
Thank you, Jaromir, for your additional clarification!
Reference(s):
commit 411d218793
Signed-off-by: Jim Warner <james.warner@comcast.net>
This should be the last of this kind of crap. I'll get
to work on some means to no longer burden a translator
with lengths requirements. Ideally each word should be
allowed to stand alone and the minimum/maximum lengths
handled programmatically when our ol' top is executed.
Signed-off-by: Jim Warner <james.warner@comcast.net>
For over a decade top has used a startup configuration
mimicking the original redhat top. This decision dates
back to when the forked Sourceforge version was trying
to win over users in battles with that ancient kludge.
Will anybody deny that those defaults are coyote ugly?
Well, it is time that top presented a more modern look
at startup, providing that no saved rcfile exists. But
just in case some distro prefers that old, comfortable
look, there's the '--disable-modern-top' build option.
[ Pssst. With the widened memory fields it turns out ]
[ the 'Mem' default window had become almost useless ]
[ on an 80x24 terminal since %CPU & COMMAND were out ]
[ of view. So some other defaults were tweaked a bit ]
[ whether or not --disable-modern-top was specified. ]
Reference(s)
http://www.freelists.org/post/procps/tops-graph-mode-saga-continues,3
Signed-off-by: Jim Warner <james.warner@comcast.net>
When startup argument parsing was recently enhanced to
account for LC_NUMERIC settings, some user input logic
dealing with numbers fails to exploit that capability.
This patch extends such enhancements to a running top.
Reference(s):
commit f7b84f45c7http://www.freelists.org/post/procps/topwatch-floating-point-input,2
Signed-off-by: Jim Warner <james.warner@comcast.net>
When those new cpu/memory graphs modes were introduced
they had global impact. In other words, the modes that
were chosen for a 'current' window affect Summary Area
appearance for every other window as well, even though
each window sets unique View_STATES/View_MEMORY flags.
I do not know how widespread the use of top's separate
window provisions is, but I do know that documentation
promises every window (field group) provides "a unique
separately configurable summary area". And even though
that promise does not include memory scaling (separate
'E' command) the graph modes are integral to 't' & 'm'
and those were already observed on a per window basis.
So this patch just takes the cpu and memory graph mode
values out of global scope in the configuration file &
gives each window its own unique pair of graph values.
Reference(s):
commit 1d171ec741
Signed-off-by: Jim Warner <james.warner@comcast.net>
Boy I hate locale stuff. For code I thought was pretty
robust, Jaromir sure proved that it wasn't. Anyway, me
thinks this commit closes some gaps and will cause top
to behave appropriately under various locale settings.
It does *not* permit top to respond to the ',' and '.'
floating point separator without regard to the locale.
It does, however, enforce proper LC_NUMERIC responses.
Let's look on this commit as an interim solution until
Jaromir can create that proposed 'fp_decode' function.
Who knows, he might even borrow some of our mkfloat().
[ An aside: the coreutils sleep and timeout programs ]
[ claim to permit floating point arguments. However, ]
[ neither one will accept the comma separator should ]
[ the locale be a country that in fact uses a comma. ]
[ In other words, with this commit we are way ahead! ]
Reference(s):
http://www.freelists.org/post/procps/topwatch-floating-point-inputhttp://www.freelists.org/post/procps/topwatch-floating-point-input,1
Signed-off-by: Jim Warner <james.warner@comcast.net>
While there was no harm done setting a handler for the
above two signals, they are in fact uncatchable. Thus,
whenever we ran with valgrind we're politely reminded.
Signed-off-by: Jim Warner <james.warner@comcast.net>
When the beginning of the Mem/Swap graphs was variable
scaling them to the current terminal's width was a bit
of a costly nightmare. So the graph size was fixed and
subject to truncation. However now that the start of a
graph can be easily predicted, I've revisited scaling.
As it turns out, any cost is minimal & mostly incurred
at an opportune time, at SIGWINCH or user interaction.
Plus, most of the apparent arithmetic is actually just
a means of documenting and will disappear thru compile
time constants in the ultimate generated machine code.
Note: those graphs will now behave just like any other
Summary Area element - they will scale from full sized
down to a terminal width of 80 columns, at which point
those displayed graphs are then subject to truncation.
Signed-off-by: Jim Warner <james.warner@comcast.net>
While the 'b' toggle remains window based (vs. global)
it should no longer require that the window be visible
and either the 'x' or 'y' toggles to be on. Previously
those requirements were intended to remind a user that
there must be something for this command to highlight.
With the introduction of graph modes (specifically the
the bar graph) the 'bold/reverse' toggle has important
implications beyond highlighting some columns or rows.
The %Cpu(s) graph and Mem portion of the memory graphs
are designed to offer a visual clue as to the separate
elements comprising them. But that separation could be
lost under some X color schemes or when top is running
without color (in monochrome mode) and the block graph
is selected. But, if the graph is then changed to bars
any separation always becomes visible whenever the 'b'
toggle is turned off. Portions then show in 'reverse'.
So from now on we'll check nothing, we'll just toggle.
[ Besides, with all the code thrown at restricting a ]
[ 'b' toggle use, it might have all been for naught. ]
[ That toggle could still be set/unset using the 'Z' ]
[ command and the color mapping screen. Geez Louise! ]
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch just beefs up the man documentation for the
new graphs modes while also reflecting the most recent
program changes, prompted by the feedback shown below.
Reference(s):
http://www.freelists.org/post/procps/latest-top-enhancements,1
Signed-off-by: Jim Warner <james.warner@comcast.net>
My original graph modes implementation made no attempt
to align the Cpu & Mem/Swap graphs. I thought, rather,
that such alignment could be best achieved by the user
using top's 'E' memory scaling command toggle. In that
way Mem/Swap prefixes could be reduced by 3 positions,
bringing the beginning '[' into line with the %Cpu(s).
If that proved to be too cumbersome a #define could be
enabled making the Mem/Swap prefix static while adding
a few padding bytes to the %Cpu line(s) for alignment.
It was those waisted bytes that were the most concern.
What I had not counted on was the fact that the memory
lines themselves might become misaligned & that became
likely with more physical memory present. That too can
be cured with the 'E' command but as scaling is raised
we soon reach a meaningless total such as '0.003' even
though the displayed % remains valid (and unchanging).
So this commit implements unconditionally what used to
be conditional. But, instead of waisting padding bytes
we'll put that space to good use with a new 'total %'.
Reference(s):
http://www.freelists.org/post/procps/latest-top-enhancements,1
commit 1d171ec741
Signed-off-by: Jim Warner <james.warner@comcast.net>
My first blush graphs modes implementation went just a
tad overboard on identifier lengths. As a result, some
program lines were getting quite long. So, this commit
will simply shorten some excessively long identifiers.
Reference(s):
http://www.freelists.org/post/procps/latest-top-enhancements
commit 1d171ec741
Signed-off-by: Jim Warner <james.warner@comcast.net>
This patch makes 't' (View_STATES) & 'm' (View_MEMORY)
commands into 4-way toggles. The two new modes provide
for two different graphs of the cpu and/or memory use.
These new capabilities are similar to those offered by
the 'htop' program. However they're aesthetically more
pleasing (to me) plus the scalings are more authentic.
Poor ol' top has long been troubled by the comparisons
offered up by the 'htop' program. Many of those things
were only true of the original redhat top while others
are no longer true of this current top program. So let
me use this commit msg to begin to correct the record.
Corrected comparisons between 'htop' & 'top' programs:
------------------------------------------------------
+ htop does not start faster, actually reverse is true
+ top offers scrolling vertically and horizontally too
. (and top offers better <Home> and <End> key support)
+ unassigned keystrokes don't subject top to any delay
. (but htop suffers that annoying ncurses <Esc> delay)
+ in top one need not type the PID to kill the process
+ in top one need not type the PID to renice a process
Some things the 'htop' program was not bragging about:
------------------------------------------------------
+ top can outperform the htop program by a wide margin
+ htop + SIGWINCH = corrupted display + restart likely
+ htop cannot preserve its screen data at suspend/exit
+ the htop column management scheme is very cumbersome
+ htop allows columns to be duplicated again and again
+ htop displays only full command lines, not pgm names
. (and that 'Command' column must always be displayed)
. (and it must always remain as the last column shown)
+ htop does not provide for any sort of command recall
+ htop's search feature does not highlight any matches
+ there is no 'find next' outside of htop search modes
+ htop does not allow Header or Process memory scaling
+ htop provides no flexibility on column justification
+ htop does not provide the means to change col widths
+ htop provides less control over colors configuration
+ htop always overwrites the rcfile with any UI change
Someday, maybe we'll provide a better comparison as an
addendum for (or replacement of) that README.top file.
Signed-off-by: Jim Warner <james.warner@comcast.net>
In anticipation of upcoming memory graphing provisions
the abbreviations 'Mem' and 'Swap' are being made into
individual translatable strings in order to be reused.
Additionally, the Mem 'used' amount will now no longer
included the 'buffers' and 'cached' values. Thus, each
Mem category becomes unique. This is the approach used
by tools such as 'htop' or the gnome 'System Monitor'.
Lastly, with that change to the 'used' category it has
been repositioned after 'free' on the Mem & Swap lines
making a comparison between 'total' and 'free' easier.
Signed-off-by: Jim Warner <james.warner@comcast.net>
For some time now, top has refrained from updating the
current number of cpus and memory totals with each and
every refresh cycle. Rather, to lessen overhead costs,
such values are updated periodically (5 min & 3 secs).
The delay in updating the cpu count was only important
with the addition of a cpu, since any loss is detected
immediately. And the large interval was chosen because
of the costs once associated with a glibc sysconf call
and an unlikely scenario of physically adding the cpu.
But the ease with which cpus can be taken offline then
placed back online under linux suggests that 5 minutes
may be too high. So, without addressing the likelihood
of that act, top is now more responsive in these ways:
1) that 5 minute interval has been reduced to 1 minute
2) any key, not just Enter/Space, refreshes cpus & mem
Note: we leave the man document as is, suggesting that
only the Enter/Space keys force an update for hotplug.
Signed-off-by: Jim Warner <james.warner@comcast.net>
. prevent any input recall overrun if window downsized
. adjust translation notes for true column hdr maximum
Signed-off-by: Jim Warner <james.warner@comcast.net>
In release 3.3.6, some commands were equipped with the
concept of a 'default pid'. The initial implementation
meant that the intuitive <Esc> key would not always be
treated as one would expect under any well behaved UI.
This patch ensures the expected <Esc> key behavior of:
terminating user input while still making possible the
necessary distinction between 'no input' & 'defaults'.
Reference(s):
http://www.freelists.org/post/procps/top-Escape-doesnt-abort-kill-command
Signed-off-by: Jim Warner <james.warner@comcast.net>
The granularity of /proc/uptime is fixed at hundredths
of a second. And, since we can cycle faster than that,
we are exposed to 'nan' when calculating elapsed time.
This commit will protect us from that outcome when the
delay interval has been set to an extremely low value.
Signed-off-by: Jim Warner <james.warner@comcast.net>
In addition to eliminating numerous single quote usage
this commit also escaped '\' a few overlooked hyphens.
And some 'unformatted' spacings were adjusted as well.
Signed-off-by: Jim Warner <james.warner@comcast.net>
The majority of changes in this commit are intended to
enable translation of top's man page. There were three
kinds of errors as seen by that po4a-updatepo program.
. a valid but unrecognized request concerning no-break
. an internally defined macro with a groff .de request
. occasional apostrophe at the beginning of some lines
With respect to the apostrophe, some have been changed
to back-tic since line placement could not be assured.
And other parts were re-flowed to avoid temptations to
escape as \' (technically an acute accent). Of course,
the opening back-tic with closing apostrophe looks odd
when ASCII, but should be rendered correctly as UTF-8.
It may yet be necessary to change the remaining single
'opening' quotes to back-tics as translation proceeds.
Should that become necessary, I intend to reduce quote
usage to the bare minimum throughout the man document.
There were also some formatting changes to enhance the
man2html output and then to other formats via htmldoc.
And, I wish to acknowledge that my meager groff skills
do not serve those programs very well at all. In other
words groff yet remains mostly incomprehensible to me.
Lastly a few content plus copyright updates were made.
Message(s):
. Unknown macro '.c2 `'. Remove it from the document, or refer to the Locale::Po4a::Man manpage to see how po4a can handle new macros.
. This page defines a new macro with '.de'. Since po4a is not a real groff parser, this is not supported.
. Unknown macro ''real time' scheduling priority.'. Remove it from the document, or refer to the Locale::Po4a::Man manpage to see how po4a can handle new macros.
Reference(s):
. oriiginal post/patch
http://www.freelists.org/post/procps/Translations-for-man-pages
Signed-off-by: Jim Warner <james.warner@comcast.net>
If a system's time is adjusted backwards, then elapsed
time could appear as negative. This yielded a negative
%CPU value. Alternately if zeros were suppressed ('0')
the result was a blank %CPU column. In both cases that
distortion would last for one display cycle or until a
user forced a display refresh via some keyboard input.
The original recommendation was trading gettimeofday()
for clock_gettime() using CLOCK_MONOTONIC. But on some
systems that might not be possible, forcing the use of
CLOCK_REALTIME instead. Not only would that complicate
the build system, but it may leave us with minus %CPU.
Another approach was to ensure that elapsed time could
never be negative. Of course, this produced distortion
of %CPU values but it would be proportionally correct.
This wasn't dissimilar to a distortion already present
should the time be adjusted forward or backward within
any 'remaining' top delay intervals. These aberrations
would be avoided with clock_gettime & CLOCK_MONOTONIC,
but that is a less than ideal solution as noted above.
This final solution, which originated down under, will
simply rely on the /proc/uptime seconds, which will be
immune to *any* tampering with the system clock. Thus,
we now have a fix for the distortion we didn't know we
suffered plus a negative %CPU that began this odyssey.
Thanks to:
sk.alvin.x@gmail.com, for the original effort
jcapik@redhat.com, for a heads up on CLOCK_MONOTONIC
csmall-procps@enc.com.au, for the best suggestion of all
Reference(s):
. original post/patch
http://www.freelists.org/post/procps/PATCH-top-use-clock-gettime-instead-of-gettimeofday
. heads up on CLOCK_MONOTONIC
http://www.freelists.org/post/procps/PATCH-top-use-clock-gettime-instead-of-gettimeofday,2
. the final solution
http://www.freelists.org/post/procps/PATCH-top-use-clock-gettime-instead-of-gettimeofday,11
Signed-off-by: Jim Warner <james.warner@comcast.net>
Minor fixes that the translator (Yuri) has found in some of the
strings. You only know how many typos and thinkos you have when
someone is trying to translate it.
Signed-off-by: Craig Small <csmall@enc.com.au>
Since its inception top has always used enumerators to
identify displayable fields. They've taken the form of
P_PID, etc. As it turns out, something has changed for
libc6-dev versions beyond 2.17-93 wherein 'P_PID' will
now be exposed via stdlib.h. I have not pinpointed the
exact cause but it may depend on header include order.
This patch just trades top's long standing 'P_' prefix
convention for that of 'EU_' (short for enumerator). I
cannot find *any* header under /usr/include/ currently
utilizing this particular three character combination.
And as a further safeguard top will henceforth include
'system' specific headers after the standard includes.
Reference(s):
http://www.freelists.org/post/procps/top-wont-compile-anymore
Signed-off-by: Jim Warner <james.warner@comcast.net>
When top originally responded to the potential libnuma
stderr write, the library was consistently called with
each refresh cycle. That, in turn, guaranteed that any
warning message would be seen at program end by virtue
of: 1) having been issued before the 2nd refresh cycle
and; 2) benefiting from inherited /dev/null buffering.
A later efficiency refactor meant the numa library may
not always be called with every refresh cycle. Rather,
it was only called if top was in one of two numa views
(the '2' or '3' toggles). That, in turn, resulted in a
loss of any warning message at program end unless numa
mode had been preserved in the rcfile. In other words,
if top was started normally then a single cycle stderr
redirect would have long passed by the time the '2' or
'3' toggle was activated. The warning message actually
was spewed but quickly lost to the full screen refresh
which follows all keyboard interactions with the user.
This commit simply moves the restoration of our stderr
redirect to program end (instead of that first display
refresh). Now, any libnuma stderr warning message will
appear as the concluding output line upon quitting top
without regard to when any numa mode view was invoked.
And since this technique might be useful in some other
context (as an example of how to 'buffer' stderr) it's
been generalized with its own #define. But to maximize
its usefulness, the original redirect should be issued
much earlier in pgm startup than top has chosen to do.
Reference(s):
. original libnuma stderr response (msg seen)
commit 35dc6dcc49
. numa refractoring for efficiency (msg lost)
commit f12c0d5c6e
Signed-off-by: Jim Warner <james.warner@comcast.net>
Apparently there are occasions when NUMA nodes may not
always be contiguous. Under such conditions nodes that
were not used would still occupy precious Summary Area
space showing 100% idle, under the '2' command toggle.
With this commit top will no longer display numa nodes
that have no associated cpu when the '2' toggle is on.
But just in case we wish to return to former behavior,
a new #define called OFF_NUMASKIP has been introduced.
And as an aside, a recent refactor mentioned below set
the stage for this patch to be 'self-tuning'. In other
words, if an inactive/non-displayed node should become
active (if even possible), then top will begin showing
such a node automatically with the next screen update.
Unfortunately, all inactive nodes now 'suppressed' are
still accessible via the '3' command. Those nodes will
just be displayed as empty (no associated cpus shown).
This is not really a top problem but more of a libnuma
and/or user deficiency. The library lacks the means to
validate a node id and the user then input a node that
was not even shown under a '2' toggle Summary display.
( too bad libnuma does not offer an 'is_node_active' )
( type function so top could warn a user when such a )
( discontinuous node was requested using his '3' cmd )
( sure, top could achieve this objective himself but )
( that would require making yet another array global )
( which i'm just not in the mood to do - besides, we )
( have already made enough concessions to libnuma.so )
Lastly, an existing #define (PRETEND_NUMA) was changed
to 'disable' node #1 so as to simulate a discontinuous
node. This allows testing of the '2' and '3' commands.
Reference(s):
http://www.spinics.net/lists/util-linux-ng/msg08671.html
. set stage for self tuning
commit f12c0d5c6e
Signed-off-by: Jim Warner <james.warner@comcast.net>
A recent change involving a one cycle stderr redirect,
to handle a libnuma potential transgression, failed to
follow normal global variable naming conventions. This
patch will capitalize the 1st letter of 'Stderr_save'.
Reference(s):
commit 35dc6dcc49
Signed-off-by: Jim Warner <james.warner@comcast.net>
Excluding those special X_XON/X_XOF enums, which might
not even be present, restore strict collating order of
all the case labels in the task_show switch statement.
Also, adjust a few sort callbacks for the same reason.
Signed-off-by: Jim Warner <james.warner@comcast.net>
