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[[!meta title="Google Summer of Code 2010"]]

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DragonFly BSD is planning to participate (pending acceptance) in the Google Summer of Code program for 2010.


Have a look at our SoC pages from [[2008|docs/developer/GoogleSoC2008/]] and [[2009|docs/developer/gsoc2009]] to get an overview about prior year's projects.  The [Projects Page](/docs/developer/ProjectsPage/) is also a potential source of ideas.


For more details on Google's Summer of Code: [Google's SoC page](http://socghop.appspot.com/)

Legend:

* Prerequisites: knowledge that the student should have before starting the project. It may be possible to acquire the knowledge in the course of the project, but the estimated difficulty would increase substantially.
* Difficulty: Estimated difficulty of the project, taking into account the complexity of the task and the time constraints of the GSoC program.
* Contact point: The person you should contact for any further information or clarifications.

#### Project ideas

##### VFS Quota System
* Create a new kernel subsystem to manage quota's in a filesystem agnostic manner by interfacing with the kernel VFS layer.
* Create filesystem-agnostic quota support tools for userland that obtain information in the same manner as eg: du(1) instead of parsing the filesystem internals directly as the existing quota tools do (see quotacheck(8), repquota(8), edquota(8), ...).
* The quota file storage can be modeled after the existing UFS code that does the same, but should use the more general bytes, files and/or directories metrics instead of the somewhat UFS-specific blocks and inodes.

Meta information:

* Prerequisites: C, introductory filesystems internals
* Difficulty: Moderate
* Contact point: Samuel J. Greear <sjg@thesjg.com>

---

##### HAMMER Data dedup
* Add a data de-duplication mechanism to HAMMER.

* Potential data matches using CRCs during pruning runs,
  verify duplicate data, collapse the B-Tree reference,
  and account for the additional ref in the allocator.

Meta information:

* Prerequisites: C, modern filesystem internals
* Difficulty: Moderate
* Contact point: dillon

---

##### Implement i386 32-bit ABI for x86_64 64-bit kernel
* Add a 32-bit syscall table which translates 32-bit
  system calls to 64-bit

* Add support for 32 bit compatibility mode operation
  and ELF binary detection.

Meta information:

* Prerequisites: C
* Difficulty: Moderate
* Contact point: dillon

---

##### Implement ARC algorithm for vnode free list
* Vnode recycling is LRU and can't efficiently handle data sets which
  exceed the maxvnode limit.

Meta information:

* Prerequisites: C, OS internals
* Difficulty: Modest
* Contact point: dillon

---

##### Implement swapoff
* We have swapon to add swap space, we need a swapoff to
  remove it.

Meta information:

* Prerequisites: C, elementary OS memory management
* Difficulty: Modest
* Contact point: dillon

---

##### Implement SHA-2 password encryption
* Implement new default encryption for master.passwd

Meta information:

* Prerequisites: C
* Difficulty: Fairly easy
* Contact point: dillon

---

##### Graphics Kernel Memory Manager Support ( GEM )
* Support dealing with graphics NUMA in kernel space for modern graphics hardware
* http://en.wikipedia.org/wiki/Graphics_Execution_Manager

Meta information:

* Prerequisites: C, knowledge of modern computer graphics system architecture
* Difficulty: Moderate
* Contact point: kernel@crater.dragonflybsd.org

---

##### Make DragonFly NUMA-aware 

* Parse related ACPI tables 
* NUMA-aware memory allocation
* References:
[ACPI SLIT parser](http://mail-index.netbsd.org/tech-kern/2009/11/23/msg006518.html)
[ACPI SRAT parser](http://mail-index.netbsd.org/tech-kern/2009/11/23/msg006517.html)
[NetBSD NUMA diff](http://www.netbsd.org/~cegger/numa2.diff)
[NetBSD NUMA x86 diff](http://www.netbsd.org/~cegger/numa_x86.diff)

Meta information:

* Prerequisites: C, introductory computer architecture
* Difficulty: Easy
* Contact point: kernel@crater.dragonflybsd.org

---

##### Volume Management based on NetBSD's port of LVM2

NetBSD reimplemented Linux's device mapper (currently only implementing
the linear, zero and error targets; Linux has support for a variety of
targets, including crypt, stripe, snap, multipath) as dm(4). Device mapper
provides the functionality on which to implement volume management; NetBSD
has imported LVM2 (which is GPL), but it is possible to create different
tools for volume management (e.g. IBM's EVMS was also built on top of device
mapper).

The goal of this project is to port both the kernel code, dm(4), and the
LVM2 userspace libraries and tools from NetBSD. If time remains, the
student should also implement a proof of concept "stripe" target or, for the
more ambitious, a "crypt" target.

A possible roadmap for this project would be

1. Port the dm(4) code

    This code uses proplib instead of binary ioctls for communicating with
userspace. Either port proplib, or convert the code to use ioctls.

1. Port the userspace tools

    Integrate the tools in our source tree using a separate vendor branch, as
is normally done for contrib software (see development(7)). Make any
DragonFlyBSD-specific changes necessary.

1. (Optional) Implement either a "stripe" target or a crypt target.

    The stripe target must be designed with robustness and extensibility in
mind, though it is not required to go all the way. It should be flexible
enough to allow for different RAID level implementations (at least 0, 1
and 5). Additionally, it should be possible to keep an internal (i.e. part
of the volume) log to speed up resyncing and parity checking. Implementing
those features would be ideal, but is not required.

    The crypt target must allow for different ciphers and cipher parameters and
should make use of our in-kernel crypto infrastructure. It is probably
necessary to do the encryption asynchronously which will require extending
the current infrastructure.

Meta information:

* Prerequisites: C, elementary OS internals
* Difficulty: Medium
* Contact point: Aggelos Economopoulos <aoiko@cc.ece.ntua.gr>

---

##### Make DragonflyBSD Tickless
* By default, the clock cyclic fires at 100 Hz, regardless of whether or not any timeouts/callouts are scheduled to fire/expire. This is suboptimal from a power efficiency standpoint, as at least one of the system's CPUs never become quiescent/idle enough to be brought into a low power state.
This work involves re-implementing the services presently provided by clock() in a tickless (or event based) fashion, eliminating the need for the system to "wake up", only to realize that there's nothing to do on an otherwise idle system.
* http://hub.opensolaris.org/bin/view/Project+tickless/lbolt

Meta information:

* Prerequisites: C, OS internals
* Difficulty: ?
* Contact point: kernel@crater.dragonflybsd.org

---

##### Make the DragonflyBSD Dispatcher Power-aware
* CPU power management as it it implemented today is relatively isolated from the rest of the system. As such, it is forced to periodically poll to measure the utilization of the system's CPU resources.
* This project extends the kernel's existing topology aware scheduling facility to bring "power domain" awareness to the dispatcher. With this awareness in place, the dispatcher can implement coalescence dispatching policy to consolidate utilization onto a smaller subset of CPU domains, freeing up other domains to be power managed. In addition to being domain aware, the dispatcher will also tend to prefer to utilize domains already running at higher power/performance states...this will increase the duration and extent to which domains can remain quiescent, improving the kernel's ability to take advantage of features like deep C-states. Because the dispatcher will track power domain utilization along the way, it can drive active domain state changes in an event driven fashion, eliminating the need for the CPUPM subsystem to poll.
* http://hub.opensolaris.org/bin/view/Project+tesla/CPUPM

Meta information:

* Prerequisites: C
* Difficulty: ?
* Contact point: kernel@crater.dragonflybsd.org

---

##### Port DragonFly to ARM platform

Meta information:

* Prerequisites: C, ARM assembly, x86 assembly
* Difficulty: Extremely hard
* Contact point: kernel@crater.dragonflybsd.org

---

##### Port valgrind to DragonFlyBSD

Valgrind is a very useful tool on a system like DragonFly that's under heavy development. Since valgrind is very target specific, a student doing the port will have to get acquainted with many low level details of the system libraries and the user<->kernel interface (system calls, signal delivery, threading...). This is a project that should appeal to aspiring systems programmers. Ideally, we would want the port to be usable with vkernel processes, thus enabling complex checking of the core kernel code.

The goal of this project is to port valgrind to the DragonFlyBSD platform so that at least the memcheck tool runs sufficiently well to be useful. This is in itself a challenging task. If time remains, the student should try to get at least a trivial valgrind tool to work on a vkernel process.

Meta information:

* Prerequisites: C, x86 assembly, low-level OS internals
* Difficulty: Hard
* Contact point: Aggelos Economopoulos <aoiko@cc.ece.ntua.gr>

---

##### Adapt pkgsrc to create a package system with dependency independence.
* Create a set of tools that modifies how the pkgsrc packages are installed, allowing for the ability to upgrade individual packages, without stopping applications that depend on said packages from working. One method of achieving this is detailed at http://www.dragonflybsd.org/goals/#packages but other methods may be possible. PC-BSD have written a tool called PBI Builder which modifies FreeBSD ports for their dependency independence PBI system, this could be used as a starting point for the DragonFly BSD tools.

Meta information:

* Prerequisites: C
* Difficulty: ?
* Contact point: kernel@crater.dragonflybsd.org

---

##### Implement virtio drivers on DragonFly to speed up DragonFly as a KVM guest
* As virtualization is coming more and more and KVM will be a strong player in that field, it might be a good idea to be the first BSD to have a virtio implementation that enables us to run at a better speed in comparison to the other BSDs and maybe close to Linux on this virtualization platform.

Meta information:

* Prerequisites: C
* Difficulty: ?
* Contact point: kernel@crater.dragonflybsd.org

---

##### Port FUSE or PUFFS from FreeBSD/NetBSD

* http://www.netbsd.org/docs/puffs/
* This would make many userspace filesystems available to DragonFly, e.g. sshfs to mention only one.

Meta information:

* Prerequisites: C, elementary OS internals
* Difficulty: Medium
* Contact point: Michael Neumann <mneumann@ntecs.de>

---

##### Make vkernels checkpointable

* See checkpt(1).
* Teach the checkpt syscall how to checkpoint multiple vmspaces.
* Add code to the vkernel which gets triggered on SIGCKPT to dump/load e.g. the current state of network drivers.
* This would allow us to save and restore or even migrate a complete DragonFly operating system running on the vkernel platform.
This could be especially handy on laptops (if we'd get X11 operating in vkernels).
* See also: http://www.dragonflybsd.org/docs/developer/CheckpointFeatures/

Meta information:

* Prerequisites: C, OS internals
* Difficulty: Medium
* Contact point: Michael Neumann <mneumann@ntecs.de>

---

##### HAMMER compression

* Compress blocks as they get written to disk.
* Only file data (rec_type == DATA) should be compressed, not meta-data.
* the CRC should be that of the uncompressed data.
* ideally you'd need to associate the uncompressed data with the buffer cache buffer somehow, so that decompression is only performed once.
* compression could be turned on a per-file or per-pfs basis.
* gzip compression would be just fine at first.

Meta information:

* Prerequisites: C, filesystem internals
* Difficulty: Medium
* Contact point: Michael Neumann <mneumann@ntecs.de>

---


##### Port usb4bsd
* Port the whole usb4bsd stuff to DragonFly, as our own usb stack is too outdated.

* The usb4bsd branch of hselasky (?) has several userland wrappers and quite good abstraction to simplify the porting.

* (is polachok doing this or not?)

Meta information:

* Prerequisites: C, OS internals
* Difficulty: Moderate
* Contact point: kernel@crater.dragonflybsd.org

---

##### Userland System V Shared Memory / Semaphore / Message Queue implementation
* Implement some or all of these subsystems in their entirety, or as completely as possible in userland using a daemon, mmap and the DragonFly umtx_sleep(2)/umtx_wakeup(2) or other userland facilities.
* Any security or other major hurdles to this approach that would likely have to be implemented in-kernel should be noted in the students application.
* Test and benchmark the new facilities with heavy SysV consumers such as PostgreSQL
* Identify performance tradeoffs made in the userland implementation versus the existing kernel implementation. If time permits identify and apply solutions to these tradeoffs so that the userland implementation performs on par with or better than the kernel implementation.

Meta information:

* Prerequisites: C, x86 assembly
* Difficulty: Moderate
* Contact point: Samuel J. Greear <sjg@thesjg.com>

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 (please add)