An example as you see in namespace SAMPLES SOAP.Demo.cls .
First, of anything else, it is an XML document.

<?xml version="1.0" encoding="UTF-8"?>
<definitions xmlns="http://schemas.xmlsoap.org/wsdl/" xmlns:SOAP-ENC="http://schemas.xmlsoap.org/soap/encoding/" xmlns:mime="http://schemas.xmlsoap.org/wsdl/mime/" xmlns:s="http://www.w3.org/2001/XMLSchema" xmlns:s0="http://tempuri.org" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/" xmlns:wsdl="http://schemas.xmlsoap.org/wsdl/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" targetNamespace="http://tempuri.org">
    <types>
        <s:schema elementFormDefault="qualified" targetNamespace="http://tempuri.org">
            <s:import namespace="http://tempuri.org/ByNameDataSet" schemaLocation="http://localhost:57772/csp/samples/SOAP.ByNameDataSet.cls?XSD"/>
            <s:import namespace="http://tempuri.org/QueryByName_DataSet" schemaLocation="http://localhost:57772/csp/samples/SOAP.Demo.QueryByName.DS.cls?XSD"/>
            <s:element name="AddInteger">
                <s:complexType>
                    <s:sequence>
                        <s:element minOccurs="0" name="Arg1" type="s:long"/>
                        <s:element minOccurs="0" name="Arg2" type="s:long"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:element name="AddIntegerResponse">
                <s:complexType>
                    <s:sequence>
                        <s:element name="AddIntegerResult" type="s:long"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:element name="DivideInteger">
                <s:complexType>
                    <s:sequence>
                        <s:element minOccurs="0" name="Arg1" type="s:long"/>
                        <s:element minOccurs="0" name="Arg2" type="s:long"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:element name="DivideIntegerResponse">
                <s:complexType>
                    <s:sequence>
                        <s:element name="DivideIntegerResult" type="s:long"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:element name="FindPerson">
                <s:complexType>
                    <s:sequence>
                        <s:element minOccurs="0" name="id" type="s:string"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:element name="FindPersonResponse">
                <s:complexType>
                    <s:sequence>
                        <s:element name="FindPersonResult" type="s0:Person"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:complexType name="Employee">
                <s:complexContent>
                    <s:extension base="s0:Person">
                        <s:sequence>
                            <s:element minOccurs="0" name="Title">
                                <s:simpleType>
                                    <s:restriction base="s:string">
                                        <s:maxLength value="50"/>
                                    </s:restriction>
                                </s:simpleType>
                            </s:element>
                            <s:element minOccurs="0" name="Salary">
                                <s:simpleType>
                                    <s:restriction base="s:long">
                                        <s:maxInclusive value="100000"/>
                                        <s:minInclusive value="0"/>
                                    </s:restriction>
                                </s:simpleType>
                            </s:element>
                            <s:element minOccurs="0" name="Notes" type="s:string"/>
                            <s:element minOccurs="0" name="Picture" type="s:base64Binary"/>
                        </s:sequence>
                    </s:extension>
                </s:complexContent>
            </s:complexType>
            <s:complexType name="Person">
                <s:sequence>
                    <s:element name="Name" type="s:string"/>
                    <s:element name="SSN" type="s:string"/>
                    <s:element minOccurs="0" name="DOB" type="s:date"/>
                    <s:element minOccurs="0" name="Home" type="s0:Address"/>
                    <s:element minOccurs="0" name="Office" type="s0:Address"/>
                    <s:element minOccurs="0" name="Spouse" type="s0:Person"/>
                    <s:element minOccurs="0" name="FavoriteColors" type="s0:ArrayOfFavoriteColorsItemString"/>
                    <s:element minOccurs="0" name="Age" type="s:long"/>
                </s:sequence>
            </s:complexType>
            <s:complexType name="Address">
                <s:sequence>
                    <s:element minOccurs="0" name="Street">
                        <s:simpleType>
                            <s:restriction base="s:string">
                                <s:maxLength value="80"/>
                            </s:restriction>
                        </s:simpleType>
                    </s:element>
                    <s:element minOccurs="0" name="City">
                        <s:simpleType>
                            <s:restriction base="s:string">
                                <s:maxLength value="80"/>
                            </s:restriction>
                        </s:simpleType>
                    </s:element>
                    <s:element minOccurs="0" name="State">
                        <s:simpleType>
                            <s:restriction base="s:string">
                                <s:maxLength value="2"/>
                            </s:restriction>
                        </s:simpleType>
                    </s:element>
                    <s:element minOccurs="0" name="Zip">
                        <s:simpleType>
                            <s:restriction base="s:string">
                                <s:maxLength value="5"/>
                            </s:restriction>
                        </s:simpleType>
                    </s:element>
                </s:sequence>
            </s:complexType>
            <s:complexType name="ArrayOfFavoriteColorsItemString">
                <s:sequence>
                    <s:element maxOccurs="unbounded" minOccurs="0" name="FavoriteColorsItem" nillable="true" type="s:string"/>
                </s:sequence>
            </s:complexType>
            <s:element name="GetByName">
                <s:complexType>
                    <s:sequence>
                        <s:element minOccurs="0" name="name" type="s:string"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:element name="GetByNameResponse">
                <s:complexType>
                    <s:sequence>
                        <s:element name="GetByNameResult" type="s0:DataSet"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:complexType name="DataSet">
                <s:sequence>
                    <s:element ref="s:schema"/>
                    <s:any/>
                </s:sequence>
            </s:complexType>
            <s:element name="GetDataSetByName">
                <s:complexType>
                    <s:sequence>
                        <s:element minOccurs="0" name="name" type="s:string"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:element name="GetDataSetByNameResponse">
                <s:complexType>
                    <s:sequence>
                        <s:element name="GetDataSetByNameResult" type="s0:ByNameDataSet"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:complexType name="ByNameDataSet">
                <s:sequence>
                    <s:any namespace="http://tempuri.org/ByNameDataSet"/>
                </s:sequence>
            </s:complexType>
            <s:element name="GetListByName">
                <s:complexType>
                    <s:sequence>
                        <s:element minOccurs="0" name="name" type="s:string"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:element name="GetListByNameResponse">
                <s:complexType>
                    <s:sequence>
                        <s:element name="GetListByNameResult" type="s0:ArrayOfPersonIdentification"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:complexType name="ArrayOfPersonIdentification">
                <s:sequence>
                    <s:element maxOccurs="unbounded" minOccurs="0" name="PersonIdentification" nillable="true" type="s0:PersonIdentification"/>
                </s:sequence>
            </s:complexType>
            <s:complexType name="PersonIdentification">
                <s:sequence>
                    <s:element minOccurs="0" name="ID" type="s:string"/>
                    <s:element name="Name" type="s:string"/>
                    <s:element name="SSN" type="s:string"/>
                    <s:element minOccurs="0" name="DOB" type="s:date"/>
                </s:sequence>
            </s:complexType>
            <s:element name="LookupCity">
                <s:complexType>
                    <s:sequence>
                        <s:element minOccurs="0" name="zip" type="s:string"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:element name="LookupCityResponse">
                <s:complexType>
                    <s:sequence>
                        <s:element name="LookupCityResult" type="s0:Address"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:element name="Mission">
                <s:complexType>
                    <s:sequence/>
                </s:complexType>
            </s:element>
            <s:element name="MissionResponse">
                <s:complexType>
                    <s:sequence>
                        <s:element name="MissionResult" type="s:string"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:element name="QueryByName">
                <s:complexType>
                    <s:sequence>
                        <s:element minOccurs="0" name="name" type="s:string"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:element name="QueryByNameResponse">
                <s:complexType>
                    <s:sequence>
                        <s:element name="QueryByNameResult" type="s0:QueryByName_DataSet"/>
                    </s:sequence>
                </s:complexType>
            </s:element>
            <s:complexType name="QueryByName_DataSet">
                <s:sequence>
                    <s:any namespace="http://tempuri.org/QueryByName_DataSet"/>
                </s:sequence>
            </s:complexType>
        </s:schema>
    </types>
    <message name="AddIntegerSoapIn">
        <part name="parameters" element="s0:AddInteger"/>
    </message>
    <message name="AddIntegerSoapOut">
        <part name="parameters" element="s0:AddIntegerResponse"/>
    </message>
    <message name="DivideIntegerSoapIn">
        <part name="parameters" element="s0:DivideInteger"/>
    </message>
    <message name="DivideIntegerSoapOut">
        <part name="parameters" element="s0:DivideIntegerResponse"/>
    </message>
    <message name="FindPersonSoapIn">
        <part name="parameters" element="s0:FindPerson"/>
    </message>
    <message name="FindPersonSoapOut">
        <part name="parameters" element="s0:FindPersonResponse"/>
    </message>
    <message name="GetByNameSoapIn">
        <part name="parameters" element="s0:GetByName"/>
    </message>
    <message name="GetByNameSoapOut">
        <part name="parameters" element="s0:GetByNameResponse"/>
    </message>
    <message name="GetDataSetByNameSoapIn">
        <part name="parameters" element="s0:GetDataSetByName"/>
    </message>
    <message name="GetDataSetByNameSoapOut">
        <part name="parameters" element="s0:GetDataSetByNameResponse"/>
    </message>
    <message name="GetListByNameSoapIn">
        <part name="parameters" element="s0:GetListByName"/>
    </message>
    <message name="GetListByNameSoapOut">
        <part name="parameters" element="s0:GetListByNameResponse"/>
    </message>
    <message name="LookupCitySoapIn">
        <part name="parameters" element="s0:LookupCity"/>
    </message>
    <message name="LookupCitySoapOut">
        <part name="parameters" element="s0:LookupCityResponse"/>
    </message>
    <message name="MissionSoapIn">
        <part name="parameters" element="s0:Mission"/>
    </message>
    <message name="MissionSoapOut">
        <part name="parameters" element="s0:MissionResponse"/>
    </message>
    <message name="QueryByNameSoapIn">
        <part name="parameters" element="s0:QueryByName"/>
    </message>
    <message name="QueryByNameSoapOut">
        <part name="parameters" element="s0:QueryByNameResponse"/>
    </message>
    <portType name="SOAPDemoSoap">
        <operation name="AddInteger">
            <input message="s0:AddIntegerSoapIn"/>
            <output message="s0:AddIntegerSoapOut"/>
        </operation>
        <operation name="DivideInteger">
            <input message="s0:DivideIntegerSoapIn"/>
            <output message="s0:DivideIntegerSoapOut"/>
        </operation>
        <operation name="FindPerson">
            <input message="s0:FindPersonSoapIn"/>
            <output message="s0:FindPersonSoapOut"/>
        </operation>
        <operation name="GetByName">
            <input message="s0:GetByNameSoapIn"/>
            <output message="s0:GetByNameSoapOut"/>
        </operation>
        <operation name="GetDataSetByName">
            <input message="s0:GetDataSetByNameSoapIn"/>
            <output message="s0:GetDataSetByNameSoapOut"/>
        </operation>
        <operation name="GetListByName">
            <input message="s0:GetListByNameSoapIn"/>
            <output message="s0:GetListByNameSoapOut"/>
        </operation>
        <operation name="LookupCity">
            <input message="s0:LookupCitySoapIn"/>
            <output message="s0:LookupCitySoapOut"/>
        </operation>
        <operation name="Mission">
            <input message="s0:MissionSoapIn"/>
            <output message="s0:MissionSoapOut"/>
        </operation>
        <operation name="QueryByName">
            <input message="s0:QueryByNameSoapIn"/>
            <output message="s0:QueryByNameSoapOut"/>
        </operation>
    </portType>
    <binding name="SOAPDemoSoap" type="s0:SOAPDemoSoap">
        <soap:binding transport="http://schemas.xmlsoap.org/soap/http" style="document"/>
        <operation name="AddInteger">
            <soap:operation soapAction="http://tempuri.org/SOAP.Demo.AddInteger" style="document"/>
            <input>
                <soap:body use="literal"/>
            </input>
            <output>
                <soap:body use="literal"/>
            </output>
        </operation>
        <operation name="DivideInteger">
            <soap:operation soapAction="http://tempuri.org/SOAP.Demo.DivideInteger" style="document"/>
            <input>
                <soap:body use="literal"/>
            </input>
            <output>
                <soap:body use="literal"/>
            </output>
        </operation>
        <operation name="FindPerson">
            <soap:operation soapAction="http://tempuri.org/SOAP.Demo.FindPerson" style="document"/>
            <input>
                <soap:body use="literal"/>
            </input>
            <output>
                <soap:body use="literal"/>
            </output>
        </operation>
        <operation name="GetByName">
            <soap:operation soapAction="http://tempuri.org/SOAP.Demo.GetByName" style="document"/>
            <input>
                <soap:body use="literal"/>
            </input>
            <output>
                <soap:body use="literal"/>
            </output>
        </operation>
        <operation name="GetDataSetByName">
            <soap:operation soapAction="http://tempuri.org/SOAP.Demo.GetDataSetByName" style="document"/>
            <input>
                <soap:body use="literal"/>
            </input>
            <output>
                <soap:body use="literal"/>
            </output>
        </operation>
        <operation name="GetListByName">
            <soap:operation soapAction="http://tempuri.org/SOAP.Demo.GetListByName" style="document"/>
            <input>
                <soap:body use="literal"/>
            </input>
            <output>
                <soap:body use="literal"/>
            </output>
        </operation>
        <operation name="LookupCity">
            <soap:operation soapAction="http://tempuri.org/SOAP.Demo.LookupCity" style="document"/>
            <input>
                <soap:body use="literal"/>
            </input>
            <output>
                <soap:body use="literal"/>
            </output>
        </operation>
        <operation name="Mission">
            <soap:operation soapAction="http://tempuri.org/SOAP.Demo.Mission" style="document"/>
            <input>
                <soap:body use="literal"/>
            </input>
            <output>
                <soap:body use="literal"/>
            </output>
        </operation>
        <operation name="QueryByName">
            <soap:operation soapAction="http://tempuri.org/SOAP.Demo.QueryByName" style="document"/>
            <input>
                <soap:body use="literal"/>
            </input>
            <output>
                <soap:body use="literal"/>
            </output>
        </operation>
    </binding>
    <service name="SOAPDemo">
        <port name="SOAPDemoSoap" binding="s0:SOAPDemoSoap">
            <soap:address location="http://localhost:57772/csp/samples/SOAP.Demo.cls"/>
        </port>
    </service>
</definitions>

Just to complete this issue.
My final solution is a VM with Ubuntu 18.04 + Docker  (as suggested by @Rich Taylor ) .
After some troubles, I moved to a Docker VOLUME as advised by  @J. Hemdal  .

Docker Volumes are typically buried in a multilevel hard to remember directory tree. 
An easy to remember symlink solved that.
And it works fine in all variations. Full durability and lightweight.
Thanks for your contributions.

Thank you @Rich Taylor !
I was sure not to be the first.  My story was more a warning not to spend to much time on it.

My workaround was an after-midnight-hack. Nobody around and I want this beast to go. devil
You know: "Once engineer, ever engineer! "
But I'm already working on suggestion #2. I have just to clean the virtual disk from old junk.

Best wishes, stay save!

I fully agree with your concerns. Especially related to parallel processing and sharding.
And modern code and design will never need this.
But there are millions of lines of old code out in the field that require these dirty tricks to survive.
And YES! You have to examine very carefully what you do.

It's a little bit like mountaineering:
Most take the cable car, some climb with ropes and a lot of fancy equipment.  While a few free climbers use nothing than their body.
You have to understand the risks and to take your decision.

#1) I'd suggest to increase the size of your LockTab as suggested by @Vic Sun 

#2) There is a class in %SYS .  ^SYS.Lock that could be useful for multiple  Lock deletes.
and as I just learned to adjust LockTab size (
SetMaxLockTableSize
https://cedocs.intersystems.com/latest/csp/documatic/%25CSP.Documatic.cls?PAGE=CLASS&LIBRARY=%25SYS&CLASSNAME=SYS.Lock


#3) ^LOCKTAB from terminal command line in %SYS also shows the Locktab