tcl-core

[TCLCORE] "array get" is very slow in Tcl9

[Paul O. <pa...@po...>]

Can anybody confirm the slow behaviour of the "array get" command in Tcl 9?
Noticed on both Windows and Linux.

Regards,
Paul

puts "Using Tcl [info patchlevel] on $tcl_platform(platform)"
catch { puts "Build-Info: [tcl::build-info]" }

set startTime [clock milliseconds]
for { set i 1 } { $i < 6000 } { incr i } {
     set arr(Key-$i) "Value-$i"
}
puts "Build time: [expr { [clock milliseconds] - $startTime }] msec"

set startTime [clock milliseconds]
set tmp [list]
foreach {key val} [array get arr "*"] {
     lappend tmp $val
}
puts "Get time  : [expr { [clock milliseconds] - $startTime }] msec"

exit 0


Using Tcl 8.6.13 on windows
Build time: 4 msec
Get time  : 3 msec

Using Tcl 8.7b1 on windows
Build-Info: 8.7b1+ecfb784c4c615a02410a54b592d4e604ece775f53bf6f6957dff581bf41c16fa.gcc-702.ilp32
Build time: 4 msec
Get time  : 4 msec

Using Tcl 9.0b1 on windows
Build-Info: 9.0b1+ec928fe7530ca16727d54953cf107dd494cc9d9b10c5d5de74434624b1270e60.gcc-702.ilp32
Build time: 5 msec
Get time  : 3029 msec

Re: [TCLCORE] "array get" is very slow in Tcl9

[Steve L. <st...@di...>]

confirmed on macOS too

-- Steve
On 8 Aug 2023 at 3:04 AM +0800, Paul Obermeier <pa...@po...>, wrote:
>
> puts "Using Tcl [info patchlevel] on $tcl_platform(platform)"
> catch { puts "Build-Info: [tcl::build-info]" }
>
> set startTime [clock milliseconds]
> for { set i 1 } { $i < 6000 } { incr i } {
>     set arr(Key-$i) "Value-$i"
> }
> puts "Build time: [expr { [clock milliseconds] - $startTime }] msec"
>
> set startTime [clock milliseconds]
> set tmp [list]
> foreach {key val} [array get arr "*"] {
>     lappend tmp $val
> }
> puts "Get time  : [expr { [clock milliseconds] - $startTime }] msec"
>
> exit 0

Re: [TCLCORE] "array get" is very slow in Tcl9

[<apn...@ya...>]

Reproduced on Windows and happens even with an empty loop body.

It appears the slowdown is caused by the DictAsListIndex function which is present in 9 but not 8.7.

In an attempt to avoid shimmering the dict to a list, it parses the string rep on every indexing operation.

I don't know the dict internal representation but given it maintains a list order (I think?), but changing DictAsListIndex to make use of that would make more sense.

In any case, the current implementation is not workable.

/Ashok



-----Original Message-----
From: Paul Obermeier <pa...@po...> 
Sent: Tuesday, August 8, 2023 12:14 AM
To: tcl...@li...
Subject: [TCLCORE] "array get" is very slow in Tcl9

Can anybody confirm the slow behaviour of the "array get" command in Tcl 9?
Noticed on both Windows and Linux.

Regards,
Paul

puts "Using Tcl [info patchlevel] on $tcl_platform(platform)"
catch { puts "Build-Info: [tcl::build-info]" }

set startTime [clock milliseconds]
for { set i 1 } { $i < 6000 } { incr i } {
     set arr(Key-$i) "Value-$i"
}
puts "Build time: [expr { [clock milliseconds] - $startTime }] msec"

set startTime [clock milliseconds]
set tmp [list]
foreach {key val} [array get arr "*"] {
     lappend tmp $val
}
puts "Get time  : [expr { [clock milliseconds] - $startTime }] msec"

exit 0


Using Tcl 8.6.13 on windows
Build time: 4 msec
Get time  : 3 msec

Using Tcl 8.7b1 on windows
Build-Info: 8.7b1+ecfb784c4c615a02410a54b592d4e604ece775f53bf6f6957dff581bf41c16fa.gcc-702.ilp32
Build time: 4 msec
Get time  : 4 msec

Using Tcl 9.0b1 on windows
Build-Info: 9.0b1+ec928fe7530ca16727d54953cf107dd494cc9d9b10c5d5de74434624b1270e60.gcc-702.ilp32
Build time: 5 msec
Get time  : 3029 msec



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Tcl-Core mailing list
Tcl...@li...
https://lists.sourceforge.net/lists/listinfo/tcl-core

Re: [TCLCORE] "array get" is very slow in Tcl9

[<apn...@ya...>]

Ticketed and temporarily fixed in trunk by disabling DictAsListIndex.

-----Original Message-----
From: apnmbx-public--- via Tcl-Core <tcl...@li...> 
Sent: Tuesday, August 8, 2023 11:42 AM
To: 'Paul Obermeier' <pa...@po...>; tcl...@li...
Subject: Re: [TCLCORE] "array get" is very slow in Tcl9

Reproduced on Windows and happens even with an empty loop body.

It appears the slowdown is caused by the DictAsListIndex function which is
present in 9 but not 8.7.

In an attempt to avoid shimmering the dict to a list, it parses the string
rep on every indexing operation.

I don't know the dict internal representation but given it maintains a list
order (I think?), but changing DictAsListIndex to make use of that would
make more sense.

In any case, the current implementation is not workable.

/Ashok



-----Original Message-----
From: Paul Obermeier <pa...@po...> 
Sent: Tuesday, August 8, 2023 12:14 AM
To: tcl...@li...
Subject: [TCLCORE] "array get" is very slow in Tcl9

Can anybody confirm the slow behaviour of the "array get" command in Tcl 9?
Noticed on both Windows and Linux.

Regards,
Paul

puts "Using Tcl [info patchlevel] on $tcl_platform(platform)"
catch { puts "Build-Info: [tcl::build-info]" }

set startTime [clock milliseconds]
for { set i 1 } { $i < 6000 } { incr i } {
     set arr(Key-$i) "Value-$i"
}
puts "Build time: [expr { [clock milliseconds] - $startTime }] msec"

set startTime [clock milliseconds]
set tmp [list]
foreach {key val} [array get arr "*"] {
     lappend tmp $val
}
puts "Get time  : [expr { [clock milliseconds] - $startTime }] msec"

exit 0


Using Tcl 8.6.13 on windows
Build time: 4 msec
Get time  : 3 msec

Using Tcl 8.7b1 on windows
Build-Info:
8.7b1+ecfb784c4c615a02410a54b592d4e604ece775f53bf6f6957dff581bf41c16fa.gcc-7
02.ilp32
Build time: 4 msec
Get time  : 4 msec

Using Tcl 9.0b1 on windows
Build-Info:
9.0b1+ec928fe7530ca16727d54953cf107dd494cc9d9b10c5d5de74434624b1270e60.gcc-7
02.ilp32
Build time: 5 msec
Get time  : 3029 msec



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Tcl-Core mailing list
Tcl...@li...
https://lists.sourceforge.net/lists/listinfo/tcl-core



_______________________________________________
Tcl-Core mailing list
Tcl...@li...
https://lists.sourceforge.net/lists/listinfo/tcl-core