In the mean time the answer is already given by Mr Maslennikov and others, but to shorten your runtime,  you could also try a "variablenless" loop, maybe this gives you some seconds more... The emphasis is on "maybe".

// if you have null-subscripts enabled
if $d(^YYY(""))!1 for i=0:1 {quit:$order(@$zr)=""} write i

// if null-subscripts are not enabled
if $d(^YYY(-9E18))!1 for i=0:1 {quit:$order(@$zr)=""} write i

// of course, you can do that on any arbitrary level too
if $d(^YYY(1,2,3,""))!1 for i=0:1 {...} write i

// the value of -9E19 ist just for explanation, use a value suitable for your needs

May I ask for the background, why do you need that node count? 

Do you have a code snippet for us? Something like

write mylist.%IsA("%ListOfDataTypes") --> 1
set item = mylist.%GetAt(2)
//
// Now the big question: what do you (want to) do with this item?
//
// do you try to lock a global: lock ^myGlobal(item) ?
// do you try to open (a possible locked) Object: set obj=##class(some.class).%OpenId(item [,4]) ?
// something else?

Somehow I don't understand your problem. If I create a simple class with a %Text property, insert some text data and then query for the word "time" I get it without problem.

Class DC.TextData Extends %Persistent
{
Property Comment As %Text(LANGUAGECLASS = "%Text.English", MAXLEN = 1000);
}

Now some data and the query

USER>d ##class(DC.TextData).%KillExtentData()

USER>s tt=##class(DC.TextData).%New(),tt.Comment="Notice, time is money." w tt.%Save()
1
USER>s tt=##class(DC.TextData).%New(),tt.Comment="It's time for a break." w tt.%Save()
1
USER>s tt=##class(DC.TextData).%New(),tt.Comment="There is no business like show business." w tt.%Save()
1
USER>d $system.SQL.Shell()
SQL Command Line Shell
----------------------------------------------------

The command prefix is currently set to: <<nothing>>.
Enter <command>, 'q' to quit, '?' for help.
[SQL]USER>>select $zversion
5.      select $zversion

Expression_1
IRIS for UNIX (Ubuntu Server LTS for x86-64) 2021.2 (Build 649U) Thu Jan 20 2022 08:49:51 EST

1 Rows(s) Affected
statement prepare time(s)/globals/cmds/disk: 0.0006s/4/140/0ms
          execute time(s)/globals/cmds/disk: 0.0008s/0/394/0ms
                          cached query class: %sqlcq.USER.cls7
---------------------------------------------------------------------------
[SQL]USER>>select * from DC.TextData where Comment %CONTAINS('time')
6.      select * from DC.TextData where Comment %CONTAINS('time')

ID      Comment
1       Notice, time is money.
2       It's time for a break.

2 Rows(s) Affected
statement prepare time(s)/globals/cmds/disk: 0.0005s/4/140/0ms
          execute time(s)/globals/cmds/disk: 0.0043s/30/4,322/0ms
                          cached query class: %sqlcq.USER.cls2
---------------------------------------------------------------------------
[SQL]USER>>quit

USER>

There are no reserved words for %Contains but there is a requirement on the field (property) type. Excuse me for my arrogance, but instead of reading the documentation everybody thinks, it's cheaper to ask a question in the developer community, to get a ready made solution. So please read this first and if something is not clear, then tell it us what you do not understand and we will help you to understand.

Maybe there are tools to dump a dynamic object, I don't know, but you can always write your own short method

/// obj: a dynamic object
/// opt: an option, how to display array elements
///      0: just show the index number
///      1: show the parenthesized index
///      2: show index number in a %Get() method
/// tag: optional, the name of the <obj> variable
/// 
ClassMethod DumpJSON(obj, opt = 2, tag = "")
{
	set itr=obj.%GetIterator(), arr=obj.%IsA("%DynamicArray") set:tag]"" tag=tag_"."
	while itr.%GetNext(.key, .val) {
		set:arr key=$case(opt, 2:"%Get("_key_")", 1:"("_key_")", :key)
		if $isobject(val), val.%IsA("%DynamicAbstractObject") {
			do ..DumpJSON(val,opt,tag_key)
		} else { write tag,key,": ",val,! }
	}
}

For ease of use, put it into the %ZLANGC00.mac, for example

%ZLANGC00   ; Command extensions

// Dump a dymanmic object
ZDDUMP(obj,opt,tag) Public { do ##class(your.utility).DumpJSON(obj,.opt,.tag) }

For the data, you mentioned above, the following will be displayed

set metaDynObj={"versionId":"2","security":[{"system":"http://terminol....}

zddump metaDynObj::"metaDynObj"
metaDynObj.versionId: 2
metaDynObj.security.%Get(0).system: http://terminology.hl7.org/CodeSystem/v3-Confidentiality
metaDynObj.security.%Get(0).code: U
metaDynObj.security.%Get(0).display: unrestricted

zddump [11,22,33]
0: 11
1: 22
2: 33

zddump [11,22,33]:1:"x"
x.(0): 11
x.(1): 22
x.(2): 33

For routines (*.int and *.mac)
- first, this is ABSOLUTE necessary, EXPORT your routines (to an file, to source-control-system, etc)
  for example: do $system.OBJ.Export(...)
- compile the routinies (which will be already done)
- delete the *.int and *.mac routinies keeping the *.obj

For classes (*.cls)
- first, this is ABSOLUTE necessary, EXPORT your classes (to an file, to source-control-system, etc)
  for example: do $system.OBJ.Export(...) do $system.OBJ.ExportPackage(...)
- compile the class(es) (which will be already done)
- put the class in deployed mode
  do $system.OBJ.MakeClassDeployed(...)
  
That's all. But DO NOT forget for the export, in elsecase you have to start over with your routines and classes by zero!

As I started with MUMPS, $H was a few days ahead of 50000, this means, I wrote my first programm (MUMPS V4b on a DEC PDP-11/34) even before ISC was founded. I have never made a direct use of those functions but, if a recall it right, they are used during the installation process (database creation, etc.) .  A quick look into the oldest docs I have (Cache 2.3) says nothing about those functions.

kill args
set args($i(args))="arg1"
set args($i(args))="arg2"
set args($i(args))="arg3"
...
set resultSet = ##class(%SQL.Statement).%ExecDirect( , sql_whereClause, args...)

RemoveDirectoryTree(some_dir) works, if it returns FALSE to you so
- either your Ensemble instance has no rights to delete files and directories
- or you feed RemoveDirrectoryTree() with a filename or with a  nonexistent directory

Try the following:

write FileUnZip,! // this should be an existing DIRECTORY
write ##class(%File).Attribute(FileUnZip),! // this should be 16 (on Windows)
write ##class(%File).RemoveDirectoryTree(FileUnZip),! // 1=removed, 0=not-removed

In some way, I wonder about your question. This is a very specific question and a correct and accurate answer can be given by Intersystems only. If you take a look on the articles here, the most of them are about other lanuages, new technologies etc. but none of Cache/IRIS internals. If you look on the questions, very often they start with "I'm new to ISC technologies, need some help". Do you really expect an answer from an newbe? Or you really expect an answer from a Kubernetes, Phyton, Angular etc. developer? On the other hand, you are an Intersystems employee, so why don't ask somebody from the developer department? What about contacting WRC? I would be ashamed to ask such a question here.

My solution, assuming that B is originated from A by some number of left or right rotations

ClassMethod RotationRight(a As %String, b As %String) As %Integer
{
    f i=0:1 ret:$e(a_a,$l(a)+1-i,*-i)=b i
}
    
ClassMethod RotationLeft(a As %String, b As %String) As %Integer
{
    f i=0:1 ret:$e(a_a,i+1,$l(a)+i)=b i
}

write ##class(%Dictionary.MethodDefinition).%OpenId("...||Rotate...").Implementation.Size

gives  40 (for RotateRight) and 38 (for RotateLeft).

I have no idea, from which error you talk.

ClassMethod MyRequest()
{
	set req = ##class(%Net.HttpRequest).%New()
	set req.Server = "msedgewebdriverstorage.blob.core.windows.net"
	set req.SSLConfiguration="Open"
	set req.Https=1
	do req.Get("/edgewebdriver/?comp=list")
	set rsp=req.HttpResponse
	
	if rsp.StatusCode=200 {
		write "Data Size: ",rsp.Data.Size,!
		write "Dumping the first 256 bytes..." zzdump rsp.Data.Read(256)
		
	} else {
		write "Return Code: ",rsp.StatusCode,!
		write "Resp.Phrase: ",rsp.ReasonPhrase,!
	}
	
	quit rsp
}

The output is just fine... no errors.

do ##class(...).MyRequest() --->

Data Size: 1832857
Dumping the first 256 bytes...
0000: EF BB BF 3C 3F 78 6D 6C 20 76 65 72 73 69 6F 6E         <?xml version
0010: 3D 22 31 2E 30 22 20 65 6E 63 6F 64 69 6E 67 3D         ="1.0" encoding=
0020: 22 75 74 66 2D 38 22 3F 3E 3C 45 6E 75 6D 65 72         "utf-8"?><Enumer
0030: 61 74 69 6F 6E 52 65 73 75 6C 74 73 20 43 6F 6E         ationResults Con
0040: 74 61 69 6E 65 72 4E 61 6D 65 3D 22 68 74 74 70         tainerName="http
0050: 73 3A 2F 2F 6D 73 65 64 67 65 77 65 62 64 72 69         s://msedgewebdri
0060: 76 65 72 73 74 6F 72 61 67 65 2E 62 6C 6F 62 2E         verstorage.blob.
0070: 63 6F 72 65 2E 77 69 6E 64 6F 77 73 2E 6E 65 74         core.windows.net
0080: 2F 65 64 67 65 77 65 62 64 72 69 76 65 72 2F 22         /edgewebdriver/"
0090: 3E 3C 42 6C 6F 62 73 3E 3C 42 6C 6F 62 3E 3C 4E         ><Blobs><Blob><N
00A0: 61 6D 65 3E 31 30 30 2E 30 2E 31 31 35 34 2E 30         ame>100.0.1154.0
00B0: 2F 65 64 67 65 64 72 69 76 65 72 5F 61 72 6D 36         /edgedriver_arm6
00C0: 34 2E 7A 69 70 3C 2F 4E 61 6D 65 3E 3C 55 72 6C         4.zip</Name><Url
00D0: 3E 68 74 74 70 73 3A 2F 2F 6D 73 65 64 67 65 77         >https://msedgew
00E0: 65 62 64 72 69 76 65 72 73 74 6F 72 61 67 65 2E         ebdriverstorage.
00F0: 62 6C 6F 62 2E 63 6F 72 65 2E 77 69 6E 64 6F 77         blob.core.window

You have to work with the Data property of the response object (which is a 1.8MB  stream)