JsonArray serialisation seems really really slow

[dannyb2018]

I am using yasson via the standard jakarta api to write out json. Performance without arrays seems ok but once there is an array suddenly it is orders of magnitude slower. I have included the code. Basically it has value that is different for different groups and so the array is a list of names of the group and then the values for the group. I have looked to see if anyone else had the same issue but apparently google search is basically useless now

    JsonObjectBuilder updateAJsonObjectBuilder = Json.createObjectBuilder();

    // get offset
    int updatedOffset = getUpdatedOffset(moneyness, triggerDelta, isCall);
    // get the collection of curves we are going to update
    // assume call
    Map<String, List<QPVolatilityPoint>> curveForSpreadGroups = callCurvesForSpreadGroups;
    // but if put use puts
    if(false == isCall)
    {
        curveForSpreadGroups = putCurvesForSpreadGroups;
    }

    // get update delta
    List<QPVolatilityPoint> fvCurve = curveForSpreadGroups.get("FV");
    QPVolatilityPoint volPointBeingUpdated = fvCurve.get(updatedOffset);

    // add moneyness
    updateAJsonObjectBuilder.add("moneyness", moneyness);

    // add update delta
    updateAJsonObjectBuilder.add("update_delta", volPointBeingUpdated.getDelta().getBigDecimal());

    // go through spread groups
    JsonArrayBuilder updatedVolPointsForSpreadGroupsAsJsonArray = Json.createArrayBuilder();
    Set<String> spreadGroupIdentifiers = curveForSpreadGroups.keySet();
    for(String currentSpreadGroupIdentifier : spreadGroupIdentifiers)
    {
        // get the current gorup
        QPPartyGroup currentSpreadCGroup = new QPPartyGroup();
        currentSpreadCGroup.parseIdentifier(currentSpreadGroupIdentifier);

        // create a record of the updated point
        JsonObjectBuilder updatedVolPointsForSpreadGroupAsJsonObjectBuilder = Json.createObjectBuilder();

        // add group name, name source and type
        updatedVolPointsForSpreadGroupAsJsonObjectBuilder.add("spread_group_name", currentSpreadCGroup.getName());
        updatedVolPointsForSpreadGroupAsJsonObjectBuilder.add("spread_group_name_source", currentSpreadCGroup.getNameSource());
        updatedVolPointsForSpreadGroupAsJsonObjectBuilder.add("spread_group_type", currentSpreadCGroup.getType());

        // add volume banded ivs
        JsonArrayBuilder volumeBandedIVsAsJsonArrayBuilder = Json.createArrayBuilder();
        // BUGBUGDB for now just zero bound ivs
        JsonObjectBuilder zeroBoundIVsAsJsonObjectBuilder = Json.createObjectBuilder();
        // add volume
        zeroBoundIVsAsJsonObjectBuilder.add("minimum_volume", 0);
        zeroBoundIVsAsJsonObjectBuilder.addNull("maximum_volume");
        // add iv
        // get the curve
        List<QPVolatilityPoint> curveForSpreadGroup = curveForSpreadGroups.get(currentSpreadGroupIdentifier);
        // get the vol point at that offset
        volPointBeingUpdated = curveForSpreadGroup.get(updatedOffset);
        // get iv and add it
        zeroBoundIVsAsJsonObjectBuilder.add("iv", volPointBeingUpdated.getImpliedVolatility().getBigDecimal());
        // add to volume bounded ivs
        volumeBandedIVsAsJsonArrayBuilder.add(zeroBoundIVsAsJsonObjectBuilder);

        // add to group update
        updatedVolPointsForSpreadGroupAsJsonObjectBuilder.add("implied_volatilities_by_volume", volumeBandedIVsAsJsonArrayBuilder);
        
        // add to list
        updatedVolPointsForSpreadGroupsAsJsonArray.add(updatedVolPointsForSpreadGroupAsJsonObjectBuilder);
    }
    // add array of updated ivs by spread group
    updateAJsonObjectBuilder.add("spread_adjusted_implied_volatilities", updatedVolPointsForSpreadGroupsAsJsonArray);