What is the advised method to use to avoid a massive load / memory usage when logic needs to retrieve DomInstances where the result could vary from 1 to 1 million (depending on the filter) ?

Option 1 (basic):

This will simply read All the DomInstances that matches the filter. So I'm expecting a big impact (timeout?) in case we are reading a lot of data.

public static List<DomInstance> GetAllDomInstanceByFieldValue(this DomHelper domHelper, FieldDescriptor fieldDescriptor, string value)

{

var filter = DomInstanceExposers.FieldValues.Field(fieldDescriptor.ID.Id.ToString()).Equal(value);

return domHelper.DomInstances.Read(filter);

}

Option 2 (paging):

This will get a set of DomInstances per go. (spreading the load somewhat)

public static List<DomInstance> GetAllDomInstanceByFieldValueByPages(this DomHelper domHelper, FieldDescriptor fieldDescriptor, string value)

{

var filter = DomInstanceExposers.FieldValues.Field(fieldDescriptor.ID.Id.ToString()).Equal(value);

var allDomInstances = new List<DomInstance>();

var pagingHelper = domHelper.DomInstances.PreparePaging(filter);

while (pagingHelper.MoveToNextPage())

{

var currentPage = pagingHelper.GetCurrentPage();

allDomInstances.AddRange(currentPage);

}

return allDomInstances;

}

How many items are retrieved via 1 page?

Option 3 (Skyline.DataMiner.Net.Tools):

I found this, but I don’t know what it does or when this should be used:

public static List<DomInstance> GetDomInstances(this DomHelper domHelper, List<Guid> instanceIds)

{

var instances = Tools.RetrieveBigOrFilter(

instanceIds,

id => DomInstanceExposers.Id.Equal(id),

filter => domHelper.DomInstances.Read(filter));

return instances;

}