| Message ID | 20240514081344.4499-1-leigh@solinno.co.uk (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | tools/xentop: fix cpu% sort order | expand |
On 14/05/2024 9:13 am, Leigh Brown wrote: > Although using integer comparison to compare doubles kind of > works, it's annoying to see domains slightly out of order when > sorting by cpu%. > > Add a compare_dbl() function and update compare_cpu_pct() to > call it. > > Signed-off-by: Leigh Brown <leigh@solinno.co.uk> > --- > tools/xentop/xentop.c | 13 ++++++++++++- > 1 file changed, 12 insertions(+), 1 deletion(-) > > diff --git a/tools/xentop/xentop.c b/tools/xentop/xentop.c > index 545bd5e96d..99199caec9 100644 > --- a/tools/xentop/xentop.c > +++ b/tools/xentop/xentop.c > @@ -85,6 +85,7 @@ static void set_delay(const char *value); > static void set_prompt(const char *new_prompt, void (*func)(const char *)); > static int handle_key(int); > static int compare(unsigned long long, unsigned long long); > +static int compare_dbl(double, double); > static int compare_domains(xenstat_domain **, xenstat_domain **); > static unsigned long long tot_net_bytes( xenstat_domain *, int); > static bool tot_vbd_reqs(xenstat_domain *, int, unsigned long long *); > @@ -422,6 +423,16 @@ static int compare(unsigned long long i1, unsigned long long i2) > return 0; > } > > +/* Compares two double precision numbers, returning -1,0,1 for <,=,> */ > +static int compare_dbl(double d1, double d2) > +{ > + if(d1 < d2) > + return -1; > + if(d1 > d2) > + return 1; > + return 0; > +} > + > /* Comparison function for use with qsort. Compares two domains using the > * current sort field. */ > static int compare_domains(xenstat_domain **domain1, xenstat_domain **domain2) > @@ -523,7 +534,7 @@ static double get_cpu_pct(xenstat_domain *domain) > > static int compare_cpu_pct(xenstat_domain *domain1, xenstat_domain *domain2) > { > - return -compare(get_cpu_pct(domain1), get_cpu_pct(domain2)); > + return -compare_dbl(get_cpu_pct(domain1), get_cpu_pct(domain2)); Oh, we were doing an implicit double->unsigned long long conversion. Over the range 0.0 to 100.0, that ought to work as expected. What kind of out-of-order are you seeing? Nevertheless, this should comparison should clearly be done using doubles. AFACT, get_cpu_pct() shouldn't ever return a NaN, so I think this simple form is fine. Oleksii: This is another bugfix to xentop, and should be considered for 4.19 at this point. ~Andrew
On 14.05.2024 14:07, Andrew Cooper wrote: > On 14/05/2024 9:13 am, Leigh Brown wrote: >> Although using integer comparison to compare doubles kind of >> works, it's annoying to see domains slightly out of order when >> sorting by cpu%. >> >> Add a compare_dbl() function and update compare_cpu_pct() to >> call it. >> >> Signed-off-by: Leigh Brown <leigh@solinno.co.uk> >> --- >> tools/xentop/xentop.c | 13 ++++++++++++- >> 1 file changed, 12 insertions(+), 1 deletion(-) >> >> diff --git a/tools/xentop/xentop.c b/tools/xentop/xentop.c >> index 545bd5e96d..99199caec9 100644 >> --- a/tools/xentop/xentop.c >> +++ b/tools/xentop/xentop.c >> @@ -85,6 +85,7 @@ static void set_delay(const char *value); >> static void set_prompt(const char *new_prompt, void (*func)(const char *)); >> static int handle_key(int); >> static int compare(unsigned long long, unsigned long long); >> +static int compare_dbl(double, double); >> static int compare_domains(xenstat_domain **, xenstat_domain **); >> static unsigned long long tot_net_bytes( xenstat_domain *, int); >> static bool tot_vbd_reqs(xenstat_domain *, int, unsigned long long *); >> @@ -422,6 +423,16 @@ static int compare(unsigned long long i1, unsigned long long i2) >> return 0; >> } >> >> +/* Compares two double precision numbers, returning -1,0,1 for <,=,> */ >> +static int compare_dbl(double d1, double d2) >> +{ >> + if(d1 < d2) >> + return -1; >> + if(d1 > d2) >> + return 1; >> + return 0; >> +} >> + >> /* Comparison function for use with qsort. Compares two domains using the >> * current sort field. */ >> static int compare_domains(xenstat_domain **domain1, xenstat_domain **domain2) >> @@ -523,7 +534,7 @@ static double get_cpu_pct(xenstat_domain *domain) >> >> static int compare_cpu_pct(xenstat_domain *domain1, xenstat_domain *domain2) >> { >> - return -compare(get_cpu_pct(domain1), get_cpu_pct(domain2)); >> + return -compare_dbl(get_cpu_pct(domain1), get_cpu_pct(domain2)); > > Oh, we were doing an implicit double->unsigned long long conversion. > Over the range 0.0 to 100.0, that ought to work as expected. What kind > of out-of-order are you seeing? > > Nevertheless, this should comparison should clearly be done using > doubles. AFACT, get_cpu_pct() shouldn't ever return a NaN, so I think > this simple form is fine. Just for completeness: INF would be similarly an issue, but hopefully cannot come back from get_cpu_pct() either. Jan
Hello, On 2024-05-14 13:07, Andrew Cooper wrote: > On 14/05/2024 9:13 am, Leigh Brown wrote: >> Although using integer comparison to compare doubles kind of >> works, it's annoying to see domains slightly out of order when >> sorting by cpu%. >> >> Add a compare_dbl() function and update compare_cpu_pct() to >> call it. >> >> Signed-off-by: Leigh Brown <leigh@solinno.co.uk> >> --- >> tools/xentop/xentop.c | 13 ++++++++++++- >> 1 file changed, 12 insertions(+), 1 deletion(-) >> >> diff --git a/tools/xentop/xentop.c b/tools/xentop/xentop.c >> index 545bd5e96d..99199caec9 100644 >> --- a/tools/xentop/xentop.c >> +++ b/tools/xentop/xentop.c >> @@ -85,6 +85,7 @@ static void set_delay(const char *value); >> static void set_prompt(const char *new_prompt, void (*func)(const >> char *)); >> static int handle_key(int); >> static int compare(unsigned long long, unsigned long long); >> +static int compare_dbl(double, double); >> static int compare_domains(xenstat_domain **, xenstat_domain **); >> static unsigned long long tot_net_bytes( xenstat_domain *, int); >> static bool tot_vbd_reqs(xenstat_domain *, int, unsigned long long >> *); >> @@ -422,6 +423,16 @@ static int compare(unsigned long long i1, >> unsigned long long i2) >> return 0; >> } >> >> +/* Compares two double precision numbers, returning -1,0,1 for <,=,> >> */ >> +static int compare_dbl(double d1, double d2) >> +{ >> + if(d1 < d2) >> + return -1; >> + if(d1 > d2) >> + return 1; >> + return 0; >> +} >> + >> /* Comparison function for use with qsort. Compares two domains >> using the >> * current sort field. */ >> static int compare_domains(xenstat_domain **domain1, xenstat_domain >> **domain2) >> @@ -523,7 +534,7 @@ static double get_cpu_pct(xenstat_domain *domain) >> >> static int compare_cpu_pct(xenstat_domain *domain1, xenstat_domain >> *domain2) >> { >> - return -compare(get_cpu_pct(domain1), get_cpu_pct(domain2)); >> + return -compare_dbl(get_cpu_pct(domain1), get_cpu_pct(domain2)); > > Oh, we were doing an implicit double->unsigned long long conversion. > Over the range 0.0 to 100.0, that ought to work as expected. What kind > of out-of-order are you seeing? Without patch: xentop - 13:29:01 Xen 4.18.2 13 domains: 1 running, 12 blocked, 0 paused, 0 crashed, 0 dying, 0 shutdown Mem: 67030640k total, 33097800k used, 33932840k free CPUs: 24 @ 3693MHz NAME STATE CPU(sec) CPU(%) MEM(k) MEM(%) MAXMEM(k) MAXMEM(%) icecream --b--- 2597 6.6 4194368 6.3 4195328 6.3 xendd --b--- 4016 5.4 524268 0.8 525312 0.8 Domain-0 -----r 1059 1.7 1048576 1.6 1048576 1.6 neon --b--- 826 1.1 2097216 3.1 2098176 3.1 blender --b--- 121 0.2 1048640 1.6 1049600 1.6 bread --b--- 69 0.1 524352 0.8 525312 0.8 bob --b--- 502 0.3 16777284 25.0 16778240 25.0 cheese --b--- 225 0.5 1048384 1.6 1049600 1.6 cassini --b--- 489 0.4 3145792 4.7 3146752 4.7 chickpea --b--- 67 0.1 524352 0.8 525312 0.8 lentil --b--- 67 0.1 262208 0.4 263168 0.4 fusilli --b--- 159 0.2 524352 0.8 525312 0.8 pizza --b--- 359 0.5 524352 0.8 525312 0.8 With patch: xentop - 13:30:17 Xen 4.18.2 13 domains: 1 running, 12 blocked, 0 paused, 0 crashed, 0 dying, 0 shutdown Mem: 67030640k total, 33097788k used, 33932852k free CPUs: 24 @ 3693MHz NAME STATE CPU(sec) CPU(%) MEM(k) MEM(%) MAXMEM(k) MAXMEM(%) xendd --b--- 4020 5.7 524268 0.8 525312 0.8 icecream --b--- 2600 3.8 4194368 6.3 4195328 6.3 Domain-0 -----r 1060 1.5 1048576 1.6 1048576 1.6 neon --b--- 827 1.1 2097216 3.1 2098176 3.1 cheese --b--- 225 0.7 1048384 1.6 1049600 1.6 pizza --b--- 359 0.5 524352 0.8 525312 0.8 cassini --b--- 490 0.4 3145792 4.7 3146752 4.7 fusilli --b--- 159 0.2 524352 0.8 525312 0.8 bob --b--- 502 0.2 16777284 25.0 16778240 25.0 blender --b--- 121 0.2 1048640 1.6 1049600 1.6 bread --b--- 69 0.1 524352 0.8 525312 0.8 chickpea --b--- 67 0.1 524352 0.8 525312 0.8 lentil --b--- 67 0.1 262208 0.4 263168 0.4 > Nevertheless, this should comparison should clearly be done using > doubles. AFACT, get_cpu_pct() shouldn't ever return a NaN, so I think > this simple form is fine. > > Oleksii: This is another bugfix to xentop, and should be considered for > 4.19 at this point. > > ~Andrew Regards, Leigh.
On 2024-05-14 13:07, Andrew Cooper wrote: > On 14/05/2024 9:13 am, Leigh Brown wrote: >> Although using integer comparison to compare doubles kind of >> works, it's annoying to see domains slightly out of order when >> sorting by cpu%. >> >> Add a compare_dbl() function and update compare_cpu_pct() to >> call it. >> >> Signed-off-by: Leigh Brown <leigh@solinno.co.uk> >> --- >> tools/xentop/xentop.c | 13 ++++++++++++- >> 1 file changed, 12 insertions(+), 1 deletion(-) >> >> diff --git a/tools/xentop/xentop.c b/tools/xentop/xentop.c >> index 545bd5e96d..99199caec9 100644 >> --- a/tools/xentop/xentop.c >> +++ b/tools/xentop/xentop.c >> @@ -85,6 +85,7 @@ static void set_delay(const char *value); >> static void set_prompt(const char *new_prompt, void (*func)(const >> char *)); >> static int handle_key(int); >> static int compare(unsigned long long, unsigned long long); >> +static int compare_dbl(double, double); >> static int compare_domains(xenstat_domain **, xenstat_domain **); >> static unsigned long long tot_net_bytes( xenstat_domain *, int); >> static bool tot_vbd_reqs(xenstat_domain *, int, unsigned long long >> *); >> @@ -422,6 +423,16 @@ static int compare(unsigned long long i1, >> unsigned long long i2) >> return 0; >> } >> >> +/* Compares two double precision numbers, returning -1,0,1 for <,=,> >> */ >> +static int compare_dbl(double d1, double d2) >> +{ >> + if(d1 < d2) >> + return -1; >> + if(d1 > d2) >> + return 1; >> + return 0; >> +} >> + >> /* Comparison function for use with qsort. Compares two domains >> using the >> * current sort field. */ >> static int compare_domains(xenstat_domain **domain1, xenstat_domain >> **domain2) >> @@ -523,7 +534,7 @@ static double get_cpu_pct(xenstat_domain *domain) >> >> static int compare_cpu_pct(xenstat_domain *domain1, xenstat_domain >> *domain2) >> { >> - return -compare(get_cpu_pct(domain1), get_cpu_pct(domain2)); >> + return -compare_dbl(get_cpu_pct(domain1), get_cpu_pct(domain2)); > > Oh, we were doing an implicit double->unsigned long long conversion. > Over the range 0.0 to 100.0, that ought to work as expected. What kind > of out-of-order are you seeing? > > Nevertheless, this should comparison should clearly be done using > doubles. AFACT, get_cpu_pct() shouldn't ever return a NaN, so I think > this simple form is fine. > > Oleksii: This is another bugfix to xentop, and should be considered for > 4.19 at this point. > > ~Andrew Perhaps I overthought it, and this approach might be better: --- a/tools/xentop/xentop.c +++ b/tools/xentop/xentop.c @@ -523,7 +523,8 @@ static double get_cpu_pct(xenstat_domain *domain) static int compare_cpu_pct(xenstat_domain *domain1, xenstat_domain *domain2) { - return -compare(get_cpu_pct(domain1), get_cpu_pct(domain2)); + return -compare(get_cpu_pct(domain1) * 100.0, + get_cpu_pct(domain2) * 100.0); } /* Prints cpu percentage statistic */
On 14/05/2024 1:36 pm, Leigh Brown wrote: > Hello, > > On 2024-05-14 13:07, Andrew Cooper wrote: >> On 14/05/2024 9:13 am, Leigh Brown wrote: >>> Although using integer comparison to compare doubles kind of >>> works, it's annoying to see domains slightly out of order when >>> sorting by cpu%. >>> >>> Add a compare_dbl() function and update compare_cpu_pct() to >>> call it. >>> >>> Signed-off-by: Leigh Brown <leigh@solinno.co.uk> >>> --- >>> tools/xentop/xentop.c | 13 ++++++++++++- >>> 1 file changed, 12 insertions(+), 1 deletion(-) >>> >>> diff --git a/tools/xentop/xentop.c b/tools/xentop/xentop.c >>> index 545bd5e96d..99199caec9 100644 >>> --- a/tools/xentop/xentop.c >>> +++ b/tools/xentop/xentop.c >>> @@ -85,6 +85,7 @@ static void set_delay(const char *value); >>> static void set_prompt(const char *new_prompt, void (*func)(const >>> char *)); >>> static int handle_key(int); >>> static int compare(unsigned long long, unsigned long long); >>> +static int compare_dbl(double, double); >>> static int compare_domains(xenstat_domain **, xenstat_domain **); >>> static unsigned long long tot_net_bytes( xenstat_domain *, int); >>> static bool tot_vbd_reqs(xenstat_domain *, int, unsigned long long *); >>> @@ -422,6 +423,16 @@ static int compare(unsigned long long i1, >>> unsigned long long i2) >>> return 0; >>> } >>> >>> +/* Compares two double precision numbers, returning -1,0,1 for <,=,> */ >>> +static int compare_dbl(double d1, double d2) >>> +{ >>> + if(d1 < d2) >>> + return -1; >>> + if(d1 > d2) >>> + return 1; >>> + return 0; >>> +} >>> + >>> /* Comparison function for use with qsort. Compares two domains >>> using the >>> * current sort field. */ >>> static int compare_domains(xenstat_domain **domain1, xenstat_domain >>> **domain2) >>> @@ -523,7 +534,7 @@ static double get_cpu_pct(xenstat_domain *domain) >>> >>> static int compare_cpu_pct(xenstat_domain *domain1, xenstat_domain >>> *domain2) >>> { >>> - return -compare(get_cpu_pct(domain1), get_cpu_pct(domain2)); >>> + return -compare_dbl(get_cpu_pct(domain1), get_cpu_pct(domain2)); >> >> Oh, we were doing an implicit double->unsigned long long conversion. >> Over the range 0.0 to 100.0, that ought to work as expected. What kind >> of out-of-order are you seeing? > > Without patch: > > xentop - 13:29:01 Xen 4.18.2 > 13 domains: 1 running, 12 blocked, 0 paused, 0 crashed, 0 dying, 0 shutdown > Mem: 67030640k total, 33097800k used, 33932840k free CPUs: 24 @ 3693MHz > NAME STATE CPU(sec) CPU(%) MEM(k) MEM(%) MAXMEM(k) MAXMEM(%) > icecream --b--- 2597 6.6 4194368 6.3 4195328 6.3 > xendd --b--- 4016 5.4 524268 0.8 525312 0.8 > Domain-0 -----r 1059 1.7 1048576 1.6 1048576 1.6 > neon --b--- 826 1.1 2097216 3.1 2098176 3.1 > blender --b--- 121 0.2 1048640 1.6 1049600 1.6 > bread --b--- 69 0.1 524352 0.8 525312 0.8 > bob --b--- 502 0.3 16777284 25.0 16778240 25.0 > cheese --b--- 225 0.5 1048384 1.6 1049600 1.6 > cassini --b--- 489 0.4 3145792 4.7 3146752 4.7 > chickpea --b--- 67 0.1 524352 0.8 525312 0.8 > lentil --b--- 67 0.1 262208 0.4 263168 0.4 > fusilli --b--- 159 0.2 524352 0.8 525312 0.8 > pizza --b--- 359 0.5 524352 0.8 525312 0.8 > > With patch: > > xentop - 13:30:17 Xen 4.18.2 > 13 domains: 1 running, 12 blocked, 0 paused, 0 crashed, 0 dying, 0 shutdown > Mem: 67030640k total, 33097788k used, 33932852k free CPUs: 24 @ 3693MHz > NAME STATE CPU(sec) CPU(%) MEM(k) MEM(%) MAXMEM(k) MAXMEM(%) > xendd --b--- 4020 5.7 524268 0.8 525312 0.8 > icecream --b--- 2600 3.8 4194368 6.3 4195328 6.3 > Domain-0 -----r 1060 1.5 1048576 1.6 1048576 1.6 > neon --b--- 827 1.1 2097216 3.1 2098176 3.1 > cheese --b--- 225 0.7 1048384 1.6 1049600 1.6 > pizza --b--- 359 0.5 524352 0.8 525312 0.8 > cassini --b--- 490 0.4 3145792 4.7 3146752 4.7 > fusilli --b--- 159 0.2 524352 0.8 525312 0.8 > bob --b--- 502 0.2 16777284 25.0 16778240 25.0 > blender --b--- 121 0.2 1048640 1.6 1049600 1.6 > bread --b--- 69 0.1 524352 0.8 525312 0.8 > chickpea --b--- 67 0.1 524352 0.8 525312 0.8 > lentil --b--- 67 0.1 262208 0.4 263168 0.4 Ah, so it's the rounding, and a straight cast discards the fractional part. I think your patch is fine, although it could do with a mention of why this goes wrong in the commit message. I'm happy to adjust on commit. ~Andrew
On Tue, 2024-05-14 at 14:52 +0100, Andrew Cooper wrote: > On 14/05/2024 1:36 pm, Leigh Brown wrote: > > Hello, > > > > On 2024-05-14 13:07, Andrew Cooper wrote: > > > On 14/05/2024 9:13 am, Leigh Brown wrote: > > > > Although using integer comparison to compare doubles kind of > > > > works, it's annoying to see domains slightly out of order when > > > > sorting by cpu%. > > > > > > > > Add a compare_dbl() function and update compare_cpu_pct() to > > > > call it. > > > > > > > > Signed-off-by: Leigh Brown <leigh@solinno.co.uk> > > > > --- > > > > tools/xentop/xentop.c | 13 ++++++++++++- > > > > 1 file changed, 12 insertions(+), 1 deletion(-) > > > > > > > > diff --git a/tools/xentop/xentop.c b/tools/xentop/xentop.c > > > > index 545bd5e96d..99199caec9 100644 > > > > --- a/tools/xentop/xentop.c > > > > +++ b/tools/xentop/xentop.c > > > > @@ -85,6 +85,7 @@ static void set_delay(const char *value); > > > > static void set_prompt(const char *new_prompt, void > > > > (*func)(const > > > > char *)); > > > > static int handle_key(int); > > > > static int compare(unsigned long long, unsigned long long); > > > > +static int compare_dbl(double, double); > > > > static int compare_domains(xenstat_domain **, xenstat_domain > > > > **); > > > > static unsigned long long tot_net_bytes( xenstat_domain *, > > > > int); > > > > static bool tot_vbd_reqs(xenstat_domain *, int, unsigned long > > > > long *); > > > > @@ -422,6 +423,16 @@ static int compare(unsigned long long i1, > > > > unsigned long long i2) > > > > return 0; > > > > } > > > > > > > > +/* Compares two double precision numbers, returning -1,0,1 for > > > > <,=,> */ > > > > +static int compare_dbl(double d1, double d2) > > > > +{ > > > > + if(d1 < d2) > > > > + return -1; > > > > + if(d1 > d2) > > > > + return 1; > > > > + return 0; > > > > +} > > > > + > > > > /* Comparison function for use with qsort. Compares two > > > > domains > > > > using the > > > > * current sort field. */ > > > > static int compare_domains(xenstat_domain **domain1, > > > > xenstat_domain > > > > **domain2) > > > > @@ -523,7 +534,7 @@ static double get_cpu_pct(xenstat_domain > > > > *domain) > > > > > > > > static int compare_cpu_pct(xenstat_domain *domain1, > > > > xenstat_domain > > > > *domain2) > > > > { > > > > - return -compare(get_cpu_pct(domain1), > > > > get_cpu_pct(domain2)); > > > > + return -compare_dbl(get_cpu_pct(domain1), > > > > get_cpu_pct(domain2)); > > > > > > Oh, we were doing an implicit double->unsigned long long > > > conversion. > > > Over the range 0.0 to 100.0, that ought to work as expected. > > > What kind > > > of out-of-order are you seeing? > > > > Without patch: > > > > xentop - 13:29:01 Xen 4.18.2 > > 13 domains: 1 running, 12 blocked, 0 paused, 0 crashed, 0 dying, 0 > > shutdown > > Mem: 67030640k total, 33097800k used, 33932840k free CPUs: 24 @ > > 3693MHz > > NAME STATE CPU(sec) CPU(%) MEM(k) MEM(%) MAXMEM(k) > > MAXMEM(%) > > icecream --b--- 2597 6.6 4194368 6.3 > > 4195328 6.3 > > xendd --b--- 4016 5.4 524268 0.8 > > 525312 0.8 > > Domain-0 -----r 1059 1.7 1048576 1.6 > > 1048576 1.6 > > neon --b--- 826 1.1 2097216 3.1 > > 2098176 3.1 > > blender --b--- 121 0.2 1048640 1.6 > > 1049600 1.6 > > bread --b--- 69 0.1 524352 0.8 > > 525312 0.8 > > bob --b--- 502 0.3 16777284 25.0 > > 16778240 25.0 > > cheese --b--- 225 0.5 1048384 1.6 > > 1049600 1.6 > > cassini --b--- 489 0.4 3145792 4.7 > > 3146752 4.7 > > chickpea --b--- 67 0.1 524352 0.8 > > 525312 0.8 > > lentil --b--- 67 0.1 262208 0.4 > > 263168 0.4 > > fusilli --b--- 159 0.2 524352 0.8 > > 525312 0.8 > > pizza --b--- 359 0.5 524352 0.8 > > 525312 0.8 > > > > With patch: > > > > xentop - 13:30:17 Xen 4.18.2 > > 13 domains: 1 running, 12 blocked, 0 paused, 0 crashed, 0 dying, 0 > > shutdown > > Mem: 67030640k total, 33097788k used, 33932852k free CPUs: 24 @ > > 3693MHz > > NAME STATE CPU(sec) CPU(%) MEM(k) MEM(%) MAXMEM(k) > > MAXMEM(%) > > xendd --b--- 4020 5.7 524268 0.8 > > 525312 0.8 > > icecream --b--- 2600 3.8 4194368 6.3 > > 4195328 6.3 > > Domain-0 -----r 1060 1.5 1048576 1.6 > > 1048576 1.6 > > neon --b--- 827 1.1 2097216 3.1 > > 2098176 3.1 > > cheese --b--- 225 0.7 1048384 1.6 > > 1049600 1.6 > > pizza --b--- 359 0.5 524352 0.8 > > 525312 0.8 > > cassini --b--- 490 0.4 3145792 4.7 > > 3146752 4.7 > > fusilli --b--- 159 0.2 524352 0.8 > > 525312 0.8 > > bob --b--- 502 0.2 16777284 25.0 > > 16778240 25.0 > > blender --b--- 121 0.2 1048640 1.6 > > 1049600 1.6 > > bread --b--- 69 0.1 524352 0.8 > > 525312 0.8 > > chickpea --b--- 67 0.1 524352 0.8 > > 525312 0.8 > > lentil --b--- 67 0.1 262208 0.4 > > 263168 0.4 > > > Ah, so it's the rounding, and a straight cast discards the fractional > part. > > I think your patch is fine, although it could do with a mention of > why > this goes wrong in the commit message. I'm happy to adjust on > commit. Feel free to merge it as I am considering it as bugfix: Release-acked-by: Oleksii Kurochko <oleksii.kurochko@gmail.com> ~ Oleksii > > ~Andrew
diff --git a/tools/xentop/xentop.c b/tools/xentop/xentop.c index 545bd5e96d..99199caec9 100644 --- a/tools/xentop/xentop.c +++ b/tools/xentop/xentop.c @@ -85,6 +85,7 @@ static void set_delay(const char *value); static void set_prompt(const char *new_prompt, void (*func)(const char *)); static int handle_key(int); static int compare(unsigned long long, unsigned long long); +static int compare_dbl(double, double); static int compare_domains(xenstat_domain **, xenstat_domain **); static unsigned long long tot_net_bytes( xenstat_domain *, int); static bool tot_vbd_reqs(xenstat_domain *, int, unsigned long long *); @@ -422,6 +423,16 @@ static int compare(unsigned long long i1, unsigned long long i2) return 0; } +/* Compares two double precision numbers, returning -1,0,1 for <,=,> */ +static int compare_dbl(double d1, double d2) +{ + if(d1 < d2) + return -1; + if(d1 > d2) + return 1; + return 0; +} + /* Comparison function for use with qsort. Compares two domains using the * current sort field. */ static int compare_domains(xenstat_domain **domain1, xenstat_domain **domain2) @@ -523,7 +534,7 @@ static double get_cpu_pct(xenstat_domain *domain) static int compare_cpu_pct(xenstat_domain *domain1, xenstat_domain *domain2) { - return -compare(get_cpu_pct(domain1), get_cpu_pct(domain2)); + return -compare_dbl(get_cpu_pct(domain1), get_cpu_pct(domain2)); } /* Prints cpu percentage statistic */
Although using integer comparison to compare doubles kind of works, it's annoying to see domains slightly out of order when sorting by cpu%. Add a compare_dbl() function and update compare_cpu_pct() to call it. Signed-off-by: Leigh Brown <leigh@solinno.co.uk> --- tools/xentop/xentop.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)