When Delete:ing a layer or a container the code was always allocating a
new slice just to remove an element from the original slice.
Profiling cri-o with c/storage showed that doing it at every delete is
pretty expensive:
```
. . 309: newContainers := []Container{}
. . 310: for _, candidate := range r.containers
{
. . 311: if candidate.ID != id {
528.17kB 528.17kB 312: newContainers =
append(newContainers, candidate)
. . 313: }
. . 314: }
. . 552: newLayers := []Layer{}
. . 553: for _, candidate := range
r.layers {
. . 554: if candidate.ID != id {
1.03MB 1.03MB 555: newLayers =
append(newLayers, candidate)
. . 556: }
. . 557: }
. . 558: r.layers = newLayers
```
This patch just filters out the element to remove from the original
slice w/o allocating a new slice. After this patch, no memory overhead
anymore is shown in the profiler.
Signed-off-by: Antonio Murdaca <runcom@redhat.com>
Add an optional *DiffOptions parameter to Diff() methods (which can be
nil), to allow overriding of default behaviors.
At this time, that's just what type of compression is applied, if we
want something other than what was recorded when the diff was applied,
but we can add more later if needed.
Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>
Add a Created field to Layer, Image, and Container structures that we
intialize when creating one of them.
Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>
Implement read-only versions of layer and image store interfaces which
allocate read-only locks and which return errors whenever a write
function is called (which should only be possible after a type
assertion, since they're not part of the read-only interfaces).
Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>
Split the LayerStore and ImageStore interfaces into read-only and
write-only subset interfaces, and make the proper stores into unions of
the read-only and write-only method sets.
Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>
We need to be able to acquire locks on storage areas which aren't
mounted read-write, which return errors when we attempt to open a file
in the mode where we can take write locks on them. This patch adds a
read-only lock type for use in those cases.
A given file can be opened for read-locking or write-locking, but not
both. Our Locker interface gains an IsReadWrite() method to let callers
tell the difference.
Based on patches by Dan Walsh <dwalsh@redhat.com>
Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>
Fix consistency errors we'd hit after creating or deleting a layer,
image, or container, by replacing the slice of items in their respective
stores with a slice of pointers to items, so that pointers in name- and
ID-based indexes don't become invalid when the slice is resized.
Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>
Daniel J Walsh