The first (lower) layer of the per-page snapshot mechanism is a page
store: its responsibility is to store immutable shareable
reference-counted memory pages independently of the snapshoting
logic. Snapshot management and representation, soft-dirty tracking
will be handled in higher layer.
Per-page shallow snapshots for the SimGrid model checker
Published:
I looked at my options to achieve efficient/cheap snapshots of the
simulated application for the Simgrid model checker using
copy-on-write. Here I look at another
solution to achieve this without using copy-on-write.
Copy-on-write snapshots for the SimGrid model checker
Published:
The SimGrid model checker
explores the graph of possible executions of
a simulated distributed application in order to verify safety and
liveness properties. The model checker needs to store the state of the
application in each node of the execution graph in order to detect
cycles. However, saving the whole state of the application at each
node of the graph leads to huge memory consumption and in some
cases most of the time is spent copying data in order to take the
snapshots of the application. We will see how we could solve this problem,
using copy-on-write.
Flamegraph
is a software which generates SVG graphics
to visualise stack-sampling based
profiles. It processes data collected with tools such as Linux perf,
SystemTap, DTrace.