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Class ImagingMemorySettings

Typed configuration options for the memory used while processing images.

Inheritance

object

Namespace: Umbraco.Cms.Core.Configuration.Models

Assembly: Umbraco.Core.dll

Syntax

public class ImagingMemorySettings

Remarks

Image processing decodes the full-resolution source into memory before it is resized, so peak memory scales with the number of images being processed at the same time rather than with the size of the response. On a host with a hard memory limit - a container, most commonly - an unbounded number of concurrent decodes will exhaust the limit and the process will be killed.

Zero means "derive a value from the memory available to the process". What each is derived as, and whether it is applied at all, belongs to the imaging package that reads these - the policy depends on the imaging library's own defaults, which this assembly knows nothing about.

Constructors

ImagingMemorySettings()

Declaration

public ImagingMemorySettings()

Properties

Enabled

Gets or sets a value indicating whether image processing memory is managed.

Declaration

public bool Enabled { get; set; }

Property Value

Type	Description
bool

Remarks

When enabled, the pool the imaging library retains between requests is capped, the number of images decoded at the same time is bounded and the size of a single decoded image is capped, on hosts where the memory available to the process is limited. Defaults to false, which leaves the imaging library's own memory behavior untouched.

MaximumConcurrentProcessing

Gets or sets the maximum number of images that may be processed at the same time.

Declaration

public int MaximumConcurrentProcessing { get; set; }

Property Value

Type	Description
int

Remarks

Requests beyond this limit wait for a place. One that does not get a place within the imaging package's wait timeout is turned away with a 503 Service Unavailable response rather than queued indefinitely. Set to zero to derive a value from the available memory and processor count.

MaximumDecodedImageMegabytes

Gets or sets the maximum size, in megabytes, of any single buffer allocated while decoding an image.

Declaration

public int MaximumDecodedImageMegabytes { get; set; }

Property Value

Type	Description
int

Remarks

A request for an image needing more than this fails rather than being served, which on a memory-limited host is preferable to exhausting the limit and taking the process with it. MaximumConcurrentProcessing bounds how many images are decoded at once against an assumed cost each; this bounds the largest allocation within one of them.

A decode makes several allocations, so this is not a ceiling on what one image costs in total. It caps the dominant one - the pixel buffer - which is enough to catch a source far larger than the host can serve. Set to zero to derive a value from the available memory.

MaximumPoolSizeMegabytes

Gets or sets the maximum size, in megabytes, of the pool the imaging library retains for reuse between requests.

Declaration

public int MaximumPoolSizeMegabytes { get; set; }

Property Value

Type	Description
int

Remarks

This memory is unmanaged, so it is not governed by any of the DOTNET_GC* settings and does not appear in the managed heap. Set to zero to derive a value from the available memory.