The SumTree implements an efficient tree data structure for
"roulette-wheel" sampling, or "sampling with fault expansion", i.e.,
sampling of trace entries / pilots without replacement and with a
picking probability proportional to the entries' sizes.
For every sample, the naive approach picks a random number between 0
and the sum of all entry sizes minus one. It then iterates over all
entries and sums their sizes until the sum exceeds the random number.
The current entry gets picked. The main disadvantage is the linear
complexity, which gets unpleasant for millions of entries.
The core idea behind the SumTree implementation is to maintain the
size sum of groups of entries, kept in "buckets". Thereby, a bucket
can be quickly jumped over. To keep bucket sizes (and thereby linear
search times) bounded, more bucket hierarchy levels are introduced
when a defined bucket size limit is reached.
Note that the current implementation is built for a pure growth phase
(when the tree gets filled with pilots from the database), followed by
a sampling phase when the tree gets emptied. It does not handle a
mixed add/remove case very smartly, although it should remain
functional.
Change-Id: If05e9700bc84761b5bc31006402641e7112b3a72
This change implements a generic registry in order to clean up import-trace's
code - it's possible (and reasonable) to use the registry for pruners as well.
Importer now extends AliasedRegisterable; all importers have been adapted
to suit the interface/abstract methods.
Each AliasedRegisterable should have at least one alias (the class' name
is a sensible choice) but can have several. The first specified alias is
the class' prime alias which can be used e.g. to list all registered objects.
Change-Id: If6daa34edce35a3b0194e4ba67ed3b44b74a49b0
The libiberty headers moved from /usr/include (and a part of binutils-dev)
to /usr/include/libiberty (libiberty-dev) between Ubuntu 13.10 and 14.04,
which made a proper cmake search module necessary. Searching still
continues working well on Debian 7.
Change-Id: I324e5ccb847e4664442d6fa7d7a027705a4f0587
Instead of hardcoded -lelf/-ldwarf use cmake modules FindLibElf/-Dwarf
and link the found libraries accordingly. This enables the user to have those
libs in arbitrary locations and link them from there.
Change-Id: I2cea3ef648a46f11b0d49d2fe0b006f76a9d4140
CMake does not support linker groups, which were used to "automatically"
fix circular dependencies between different static FAIL* libraries and
the ordering of dynamic external libraries broke linking.
CMake can however correctly invoke the linker if dependencies are decribed
correctly (even if circular). This required changing all add_dependencies
calls between libraries to target_link_libraries (which creates a link-time
dependency) and linking all experiments to fail-sal.
Change-Id: I3a0d5dddb9b3d963ef538814e20d6b3de85d4ec5
Instead of hardcoded -lelf/-ldwarf use cmake modules FindLibElf/-Dwarf
and link the found libraries accordingly. This enables the user to have those
libs in arbitrary locations and link them from there.
Change-Id: I2cea3ef648a46f11b0d49d2fe0b006f76a9d4140
We now use boost::icl::interval_set internally, consuming extremely
lower amounts of memory. boost::icl was introduced with Boost 1.46;
Debian 7.0 comes with 1.49, so this dependency should be no problem
anymore.
Both the class interface and the memory-map file format stay the same.
Change-Id: I38e8148384c90aa493984d0f6280817df00f1702
If the --debug option is set, the line number table of the elf binary will
be imported into the database. The information will be stored in the
"dbg_mapping" table.
If the --sources option is set, the source files will be imported
into the database. Only the files that were actually used in the
elf binary will be imported.
Change-Id: I0e9de6b456bc42b329c1700c25e5839d9552cdbb
As for the pandaboard to navigate fast to the injection
instruction we need to deliver a hop chain to the fail-client,
this commit adds a generic wrapper for a injection point.
For now we have only the two options hop chain and instruction
offset, so it is activated via a cmake ON/OFF switch.
Change-Id: Ic01a07a30ac386d4316e6d6d271baf1549db966a
Unfortunately this implicit dependency is currently not resolved anywhere
else (e.g., FindBoost.cmake), although the 'net heavily discusses this
issue.
Change-Id: I8a7c8518394cdba27e591fed250623011d988067
The LLVM Disassembler infrastructure can be used to analyze many kinds
of ELF Binaries. For every instruction the used and defined registers
is available as well as information about the instruction itself.
Change-Id: I9cc89b6c116ceff7b5143a6f179ae31c4e994d2d
The DatabaseCampaign interacts with the MySQL tables that are created
by the import-trace and prune-trace tools. It does offer all
unfinished experiment pilots from the database to the
fail-clients. Those clients send back a (by the experiment) defined
protobuf message as a result. The custom protobuf message does have to
need the form:
import "DatabaseCampaignMessage.proto";
message ExperimentMsg {
required DatabaseCampaignMessage fsppilot = 1;
repeated group Result = 2 {
// custom fields
required int32 bitoffset = 1;
optional int32 result = 2;
}
}
The DatabaseCampaignMessage is the pilot identifier from the
database. For each of the repeated result entries a row in a table is
allocated. The structure of this table is constructed (by protobuf
reflection) from the description of the message. Each field in the
Result group becomes a column in the result table. For the given
example it would be:
CREATE TABLE result_ExperimentMessage(
pilot_id INT,
bitoffset INT NOT NULL,
result INT,
PRIMARY_KEY(pilot_id)
)
Change-Id: I28fb5488e739d4098b823b42426c5760331027f8
The import tool does support the following import strategies:
- BasicImporter: generates def-use equivalence classes for read and
write memory accesses
- DCiAOKernelImporter: generates equivalence classes for read access in
the ciao kernel space.
Change-Id: I8960561d3e14dcf5dffa3ff7a59b61a5e8f7e719
The disassembler disassembles an elf file with
an external objdump tool.
The architecture specific objdump must be configured
via cmake (ARCH_TOOL_PREFIX), e.g. arm-none-eabi- for
arm-none-eabi-objdump.
This is a precaution to avoid current and future naming conflicts with
common system libraries. libutil (part of libc) is the first, but probably
not the last example that already caused trouble twice.
git-svn-id: https://www4.informatik.uni-erlangen.de/i4svn/danceos/trunk/devel/fail@1614 8c4709b5-6ec9-48aa-a5cd-a96041d1645a
The FailBochs client is not linked by the Bochs build system anymore, but
by our cmake scripts (make fail-client):
- All Bochs libraries are merged into libfailbochs.a (a new target
within the Bochs Autotools scripts).
- The previous libfail.a is *not* a merge of all Fail* libraries anymore,
but pulls these in via library dependencies.
Additionally I did a lot of build system cleanup, e.g. additional external
libraries may now be pulled in where they're needed.
git-svn-id: https://www4.informatik.uni-erlangen.de/i4svn/danceos/trunk/devel/fail@1390 8c4709b5-6ec9-48aa-a5cd-a96041d1645a
