general trend in responstime indicating? - memory-leaks

Question

I have a simple VUGen navigation script recorded using URL mode and pasted in below.
I have two questions:
Is it not possible to use web_reg_find() in URL mode recorded scripts?
When placing a verification (web_reg_find) before a step in the script where I know that i.e. a text is to appear. The Generation log only inform me that web_reg_find was succesfull (not the way I am used to with HTML mode and when the Generation log typically exposes the value itself also).
When running the below script as a sceanrio in the Controller With 2 users, after 10 minutes of running the transaction time peaks, the CPU usage in JVM peaks (99,9%) and Memory is also "maxed-out". It is typical to think that this has to do with heap and GC settings ++.
But is it possible that the script itself is making this happen. More details that can lead to the script being the reason for the peak in responstime/memeory/cpu usage is that the application I am testing is not integrated with any services at all, all being mocked around it. I also just use one user to log in for all mye requests, due to this being mocked and I am getting the same response everytime. But it does throw error on any transactions. There is also no logout/cleanup logic implemented wich could lead to accumulated sessions on the webserver so that may be the case.
My next step is to use JVisualVM to dig into the high CPU usage after some time when the peaking happens.
So my general question is: Could this phenomen, as in after 10 mins responsetime peakes, and memory/CPU consumption peaks on the WAS (actually a JBoss), be due to something with the script itself? Anyone having experienced that their script is the source of this?
Action()
{
//Saving sessionID i in parameter for further manual correlation during the script
web_reg_save_param_ex("ParamName=SessionID",
"LB=jsessionid=",
"RB=?",
SEARCH_FILTERS,
"Scope=Headers",
LAST);
//lr_output_message("Sesjons ID: %s", lr_eval_string ("+{SessionID}"));
web_url("something",
"URL={url}/something/",
"Resource=0",
"RecContentType=text/html",
"Referer=",
"Snapshot=t1.inf",
"Mode=HTTP",
LAST);
web_concurrent_start(NULL);
web_url("modig-ver-1359533772000.css",
"URL={url}/something/css/modig-ver-1359533772000.css",
"Resource=1",
"RecContentType=text/css",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t2.inf",
LAST);
web_url("bootstrap-transition-ver-1359533772000.js",
"URL={url}/something/js/bootstrap/bootstrap-transition-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t3.inf",
LAST);
web_url("bootstrap-alert-ver-1359533772000.js",
"URL={url}/something/js/bootstrap/bootstrap-alert-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t4.inf",
LAST);
web_url("datepicker-ver-1360590665000.css",
"URL={url}/something/css/datepicker-ver-1360590665000.css",
"Resource=1",
"RecContentType=text/css",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t5.inf",
LAST);
web_url("ViseForslagTilSomethingPage-ver-1360590665000.css",
"URL={url}/something/css/ViseForslagTilSomethingPage-ver-1360590665000.css",
"Resource=1",
"RecContentType=text/css",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t6.inf",
LAST);
web_url("bootstrap-carousel-ver-1359533772000.js",
"URL={url}/something/js/bootstrap/bootstrap-carousel-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t7.inf",
LAST);
web_url("bootstrap-button-ver-1359533772000.js",
"URL={url}/something/js/bootstrap/bootstrap-button-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t8.inf",
LAST);
web_url("GettingreadyForSomethingPage-ver-1360590665000.css",
"URL={url}/something/css/GettingreadyForSomethingPage-ver-1360590665000.css",
"Resource=1",
"RecContentType=text/css",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t9.inf",
LAST);
web_url("bootstrap-collapse-ver-1359533772000.js",
"URL={url}/something/js/bootstrap/bootstrap-collapse-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t10.inf",
LAST);
web_url("bootstrap-tooltip-ver-1359533772000.js",
"URL={url}/something/js/bootstrap/bootstrap-tooltip-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t11.inf",
LAST);
web_url("bootstrap-dropdown-ver-1359533772000.js",
"URL={url}/something/js/bootstrap/bootstrap-dropdown-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t12.inf",
LAST);
web_url("bootstrap-modal-ver-1359533772000.js",
"URL={url}/something/js/bootstrap/bootstrap-modal-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t13.inf",
LAST);
web_url("VurderePiceofshitListePanel-ver-1360590665000.css",
"URL={url}/something/css/VurderePiceofshitListePanel-ver-1360590665000.css",
"Resource=1",
"RecContentType=text/css",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t14.inf",
LAST);
web_url("bootstrap-popover-ver-1359533772000.js",
"URL={url}/something/js/bootstrap/bootstrap-popover-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t15.inf",
LAST);
web_url("bootstrap-scrollspy-ver-1359533772000.js",
"URL={url}/something/js/bootstrap/bootstrap-scrollspy-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t16.inf",
LAST);
web_url("bootstrap-tab-ver-1359533772000.js",
"URL={url}/something/js/bootstrap/bootstrap-tab-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t17.inf",
LAST);
web_url("bootstrap-affix-ver-1359533772000.js",
"URL={url}/something/js/bootstrap/bootstrap-affix-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t18.inf",
LAST);
web_url("bootstrap-datepicker-ver-1360590665000.js",
"URL={url}/something/js/bootstrap-datepicker-ver-1360590665000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t19.inf",
LAST);
web_url("BasePage-ver-1360590665000.css",
"URL={url}/something/css/BasePage-ver-1360590665000.css",
"Resource=1",
"RecContentType=text/css",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t20.inf",
LAST);
web_url("jquery.placeholder-local-modernisering-version-ver-1360590665000.js",
"URL={url}/something/js/jquery.placeholder-local-modernisering-version-ver-1360590665000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t21.inf",
LAST);
web_url("bootstrap-typeahead-ver-1359533772000.js",
"URL={url}/something/js/bootstrap/bootstrap-typeahead-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t22.inf",
LAST);
web_url("BasePage-ver-1360590665000.js",
"URL={url}/something/js/BasePage-ver-1360590665000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t23.inf",
LAST);
web_url("GettingreadyForSomethingPage-ver-1360590665000.js",
"URL={url}/something/js/GettingreadyForSomethingPage-ver-1360590665000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t24.inf",
LAST);
web_url("BstreetPanel-ver-1360590665000.js",
"URL={url}/something/js/BstreetPanel-ver-1360590665000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t25.inf",
LAST);
web_url("wicket-debugbar-ver-1355500350000.css",
"URL={url}/something/wicket/resource/org.apache.wicket.devutils.debugbar.DebugBar/wicket-debugbar-ver-1355500350000.css",
"Resource=1",
"RecContentType=text/css",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t26.inf",
LAST);
web_url("BstreetPanel-ver-1360590665000.css",
"URL={url}/something/css/BstreetPanel-ver-1360590665000.css",
"Resource=1",
"RecContentType=text/css",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t27.inf",
LAST);
web_url("wicket-debugbar-ver-1355500350000.js",
"URL={url}/something/wicket/resource/org.apache.wicket.devutils.debugbar.DebugBar/wicket-debugbar-ver-1355500350000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t28.inf",
LAST);
web_url("FatteSomethingPage-ver-1360590665000.css",
"URL={url}/something/css/FatteSomethingPage-ver-1360590665000.css",
"Resource=1",
"RecContentType=text/css",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t29.inf",
LAST);
web_url("PiceofshitPanel-ver-1360590665000.js",
"URL={url}/something/js/PiceofshitPanel-ver-1360590665000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t30.inf",
LAST);
web_url("wicket-ver-1355500350000.png",
"URL={url}/something/wicket/resource/org.apache.wicket.devutils.debugbar.DebugBar/wicket-ver-1355500350000.png",
"Resource=1",
"RecContentType=image/png",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t31.inf",
LAST);
web_url("bug-ver-1355500350000.png",
"URL={url}/something/wicket/resource/org.apache.wicket.devutils.inspector.InspectorPage/bug-ver-1355500350000.png",
"Resource=1",
"RecContentType=image/png",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t32.inf",
LAST);
web_url("remove-ver-1355500350000.png",
"URL={url}/something/wicket/resource/org.apache.wicket.devutils.debugbar.DebugBar/remove-ver-1355500350000.png",
"Resource=1",
"RecContentType=image/png",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t33.inf",
LAST);
web_url("jquery-1.8.2-ver-1359533772000.js",
"URL={url}/something/js/jquery/jquery-1.8.2-ver-1359533772000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t34.inf",
LAST);
web_url("harddrive-ver-1355500350000.png",
"URL={url}/something/wicket/resource/org.apache.wicket.devutils.debugbar.SessionSizeDebugPanel/harddrive-ver-1355500350000.png",
"Resource=1",
"RecContentType=image/png",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t35.inf",
LAST);
web_concurrent_end(NULL);
web_concurrent_start(NULL);
web_url("prosessteg_gettingready.png",
"URL={url}/something/css/images/prosessteg_gettingready.png",
"Resource=1",
"RecContentType=image/png",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t36.inf",
LAST);
web_url("somelogo.jpg",
"URL={url}/something/css/images/somelogo.jpg",
"Resource=1",
"RecContentType=image/jpeg",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t37.inf",
LAST);
web_url("glyphicons-halflings-white.png",
"URL={url}/something/img/glyphicons-halflings-white.png",
"Resource=1",
"RecContentType=image/png",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t38.inf",
LAST);
web_concurrent_end(NULL);
web_reg_save_param_ex(
"ParamName=someOtherThingsId",
"LB=something/someOtherThing/",
"RB=/gettingready",
SEARCH_FILTERS,
"Scope=Headers",
LAST);
//lr_output_message("SomeOtherThings ID:", lr_eval_string ("{someOtherThingsId}"));
lr_think_time(3);
lr_start_transaction("Logg inn");
web_submit_data("create;jsessionid=+{SessionID}",
"Action={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0-1.IFormSubmitListener-createeSomeOtherThingForm",
"Method=POST",
"RecContentType=text/html",
"Referer={url}/something/someOtherThing/create;jsessionid=+{SessionID}?0",
"Snapshot=t39.inf",
"Mode=HTTP",
ITEMDATA,
"Name=neste", "Value=x", ENDITEM,
"Name=fnr", "Value={fnr}", ENDITEM,
"Name=someOtherThingsidbuse", "Value=", ENDITEM,
"Name=userId", "Value=P114818", ENDITEM,
"Name=authenticationLevel", "Value=3", ENDITEM,
"Name=identType", "Value=internal", ENDITEM,
"Name=consumerId", "Value=something", ENDITEM,
LAST);
web_concurrent_start(NULL);
web_url("modal-ver-1355500286000.js",
"URL={url}/something/wicket/resource/org.apache.wicket.extensions.ajax.markup.html.modal.ModalWindow/res/modal-ver-1355500286000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/gettingready?3",
"Snapshot=t40.inf",
LAST);
web_url("wicket-ajax-jquery-ver-1355500070000.js",
"URL={url}/something/wicket/resource/org.apache.wicket.ajax.AbstractDefaultAjaxBehavior/res/js/wicket-ajax-jquery-ver-1355500070000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/gettingready?3",
"Snapshot=t41.inf",
LAST);
web_url("wicket-event-jquery-ver-1355500070000.js",
"URL={url}/something/wicket/resource/org.apache.wicket.ajax.AbstractDefaultAjaxBehavior/res/js/wicket-event-jquery-ver-1355500070000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/gettingready?3",
"Snapshot=t42.inf",
LAST);
web_url("modal-ver-1355500286000.css",
"URL={url}/something/wicket/resource/org.apache.wicket.extensions.ajax.markup.html.modal.ModalWindow/res/modal-ver-1355500286000.css",
"Resource=1",
"RecContentType=text/css",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/gettingready?3",
"Snapshot=t43.inf",
LAST);
web_url("wicket-ajax-jquery-debug-ver-1355500070000.js",
"URL={url}/something/wicket/resource/org.apache.wicket.ajax.AbstractDefaultAjaxBehavior/res/js/wicket-ajax-jquery-debug-ver-1355500070000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/gettingready?3",
"Snapshot=t44.inf",
LAST);
web_concurrent_end(NULL);
web_url("glyphicons-halflings.png",
"URL={url}/something/img/glyphicons-halflings.png",
"Resource=1",
"RecContentType=image/png",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/gettingready?3",
"Snapshot=t45.inf",
LAST);
lr_end_transaction("Logg inn",LR_AUTO);
lr_think_time(5);
lr_start_transaction("Neste Gettingready something");
web_url("gettingready",
"URL={url}/something/someOtherThing/{someOtherThingsId}/gettingready?2-1.IBehaviorListener.0-neste&_=1361189220848",
"Resource=0",
"RecContentType=text/xml",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/gettingready?3",
"Snapshot=t46.inf",
"Mode=HTTP",
LAST);
web_url("vurderepiceofshit",
"URL={url}/something/someOtherThing/{someOtherThingsId}/vurderepiceofshit",
"Resource=0",
"RecContentType=text/html",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/gettingready?3",
"Snapshot=t47.inf",
"Mode=HTTP",
LAST);
web_url("AjaxFormChoiceComponentUpdatingBehavior-ver-1355500070000.js",
"URL={url}/something/wicket/resource/org.apache.wicket.ajax.form.AjaxFormChoiceComponentUpdatingBehavior/AjaxFormChoiceComponentUpdatingBehavior-ver-1355500070000.js",
"Resource=1",
"RecContentType=text/javascript",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/vurderepiceofshit?5",
"Snapshot=t48.inf",
LAST);
web_concurrent_start(NULL);
web_url("icon_ikke_ok.png",
"URL={url}/something/css/images/icon_ikke_ok.png",
"Resource=1",
"RecContentType=image/png",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/vurderepiceofshit?5",
"Snapshot=t49.inf",
LAST);
web_url("icon_ok.png",
"URL={url}/something/css/images/icon_ok.png",
"Resource=1",
"RecContentType=image/png",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/vurderepiceofshit?5",
"Snapshot=t50.inf",
LAST);
web_url("Prosessteg_vurdere_piceofshit.png",
"URL={url}/something/css/images/Prosessteg_vurdere_piceofshit.png",
"Resource=1",
"RecContentType=image/png",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/vurderepiceofshit?5",
"Snapshot=t51.inf",
LAST);
web_url("icon_vurderes.png",
"URL={url}/something/css/images/icon_vurderes.png",
"Resource=1",
"RecContentType=image/png",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/vurderepiceofshit?5",
"Snapshot=t52.inf",
LAST);
web_concurrent_end(NULL);
lr_end_transaction("Neste Gettingready something",LR_AUTO);
lr_think_time(5);
lr_start_transaction("Velg Oppfyllt og trykk lagre");
web_submit_data("vurderepiceofshit_2",
"Action={url}/something/someOtherThing/{someOtherThingsId}/vurderepiceofshit?3-1.IBehaviorListener.0-vurderePiceofshitListe-vurderePiceofshitRepeater-4-vurderePiceofshitListItem-piceofshitHoved-innerPanel-piceofshitDetaljer-piceofshitForm-piceofshitsregelValg",
"Method=POST",
"RecContentType=text/xml",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/vurderepiceofshit?5",
"Snapshot=t53.inf",
"Mode=HTTP",
ITEMDATA,
"Name=piceofshitsregelValg", "Value=OPPFYLT", ENDITEM,
LAST);
web_submit_data("vurderepiceofshit_3",
"Action={url}/something/someOtherThing/{someOtherThingsId}/vurderepiceofshit?4-1.IFormSubmitListener-vurderePiceofshitListe-vurderePiceofshitRepeater-4-vurderePiceofshitListItem-piceofshitHoved-innerPanel-piceofshitDetaljer-piceofshitForm",
"Method=POST",
"RecContentType=text/html",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/vurderepiceofshit?5",
"Snapshot=t54.inf",
"Mode=HTTP",
ITEMDATA,
"Name=piceofshitForm33_hf_0", "Value=", ENDITEM,
"Name=piceofshitsregelValg", "Value=OPPFYLT", ENDITEM,
LAST);
lr_end_transaction("Velg Oppfyllt og trykk lagre",LR_AUTO);
lr_think_time(5);
lr_start_transaction("Velg neste etter Oppfyllt Uttak av pensjon");
web_url("Neste",
"URL={url}/something/someOtherThing/{someOtherThingsId}/vurderepiceofshit?7-1.ILinkListener-neste",
"Resource=0",
"RecContentType=text/html",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/vurderepiceofshit?7",
"Snapshot=t55.inf",
"Mode=HTTP",
LAST);
lr_end_transaction("Velg neste etter Oppfyllt Uttak av pensjon",LR_AUTO);
lr_think_time(5);
lr_start_transaction("Send til beslutning");
web_url("Send til beslutning",
"URL={url}/something/someOtherThing/{someOtherThingsId}/forslagsomething?8-1.ILinkListener-neste",
"Resource=0",
"RecContentType=text/html",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/forslagsomething?8",
"Snapshot=t56.inf",
"Mode=HTTP",
LAST);
lr_end_transaction("Send til beslutning",LR_AUTO);
lr_think_time(5);
lr_start_transaction("Huk av for godkjent beslutning");
web_submit_data("fattesomething",
"Action={url}/something/someOtherThing/{someOtherThingsId}/fattesomething?9-1.IBehaviorListener.0-tabbedPanel-content-panels-0-panel-tableBody-kontrollpunkter-0-kontrollpunkt-beslutningForm-valgtBeslutning",
"Method=POST",
"RecContentType=text/xml",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/fattesomething?9",
"Snapshot=t57.inf",
"Mode=HTTP",
ITEMDATA,
"Name=valgtBeslutning", "Value=0", ENDITEM,
LAST);
lr_end_transaction("Huk av for godkjent beslutning",LR_AUTO);
lr_think_time(5);
lr_start_transaction("Godkjenn og iverksett");
web_url("fattesomething_2",
"URL={url}/something/someOtherThing/{someOtherThingsId}/fattesomething?9-1.ILinkListener-godkjenn",
"Resource=0",
"RecContentType=text/html",
"Referer={url}/something/someOtherThing/{someOtherThingsId}/fattesomething?9",
"Snapshot=t58.inf",
"Mode=HTTP",
LAST);
web_url("thatsallfolks.jpg",
"URL={url}/something/css/images/thatsallfolks.jpg",
"Resource=1",
"RecContentType=image/jpeg",
"Referer={url}/something/wicket/bookmarkable/no.nav.something.web.pages.terminus.TerminusPage?someOtherThingId={someOtherThingsId}",
"Snapshot=t59.inf",
LAST);
lr_end_transaction("Godkjenn og iverksett",LR_AUTO);
return 0;

Answer 1

web_reg_find() context is the next call. With HTML mode that call made include subcalls. You need to be very careful on placement of web_reg_*() calls in URL mode to ensure that you have the proper context. And yes, web_reg_find() will execute successfully every single time even if it does not find the value. You will need to manually check in your code for how many instances of the text were found in the call.
As you your larger question, can a script cause an error. In general, yes it can. If you are exercising an interface in an out of spec fashion from its intended use then the likelihood is high for false errors to be generated. What are some of the common causes, using the same login credentials for multiple users where all users would be distinct in production, users operating against the same set of data causing locking and blocking issues where in production each of the datasets would be distinct, having no think time or iteration time (essentially blasting the interface), etc...
If you exercise the interface in question in an in-spec manner, the same way in which a user will be exercising the interface, and you find errors then the errors are directly related to the code in use on the server. I would recommend leveraging any number of commercial or open source JVM diagnostic utilities to see where the resources are being consumed and pass that information back to the developers.