| Commit message (Collapse) | Author | Age | Files | Lines |
|---|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
Congestion avoidance is a property of the layer, orthogonal to ARQ
and to flow control: FRCP retransmits and lets the peer pace the
sender, per flow, end-to-end; the IPCP paces path aggregates. Each
signal means one thing: a loss triggers a retransmission, a mark
means congestion, the peer window means a slow receiver. Every flow
is paced by the same rate law whatever its QoS, so a greedy raw
sender shares a bottleneck fairly with a reliable stream.
The unit of control is the (destination address, QoS cube)
aggregate: all flows toward that destination share one controller
and one rate; a start-time fair-queuing pacer divides the rate
across them by deadline instead of blocking the send path, and a
new flow rides the aggregate's estimates at its current rate, with
no probing of its own. Slow start runs once per aggregate.
The congestion signal is a multi-bit magnitude: forwarders mark
packets with their standing queue depth, MAX-combined across hops,
so a packet carries the deepest queue on its path. The receiver
feeds back a time-integral mean over a window that adapts to the
flow's byte rate, measuring a slow flow with the same fidelity as a
fast one. The sender runs AIMD scaled by elapsed wall-clock time,
which makes the steady-state allocation RTT-independent.
The PCI gains one byte: the path capacity as a quarter-log2 code.
Forwarders estimate their egress rate from busy-period drain and
MIN-stamp the byte, the receiver returns the window minimum with
its feedback, and the sender scales its rate floor and additive
slope to the bottleneck (C / 32). A deep cut implies a backlogged
bottleneck and a backlogged bottleneck advertises its capacity, so
the scaled floor is live exactly when recovery needs it: the probe
heals a halving in seconds at any link rate, and the floor bounds
the deepest hole to a factor 32 below the bottleneck.
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
| |
|
|
|
| |
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
This is a first step towards the Secure Shared Memory (SSM)
infrastructure for Ouroboros, which will allow proper resource
separation for non-privileged processes.
This replaces the rdrbuff (random-deletion ring buffer) PoC allocator
with a sharded slab allocator for the packet buffer pool to avoid the
head-of-line blocking behaviour of the rdrb and reduce lock contention
in multi-process scenarios. Each size class contains multiple
independent shards, allowing parallel allocations without blocking.
- Configurable shard count per size class (default: 4, set via
SSM_POOL_SHARDS in CMake). The configured number of blocks are
spread over the number of shards. As an example:
SSM_POOL_512_BLOCKS = 768 blocks total
These 768 blocks are shared among 4 shards
(not 768 × 4 = 3072 blocks)
- Lazy block distribution: all blocks initially reside in shard 0
and naturally migrate to process-local shards upon first
allocation and subsequent free operations
- Fallback with work stealing: processes attempt allocation from
their local shard (pid % SSM_POOL_SHARDS) first, then steal
from other shards if local is exhausted, eliminating
fragmentation while maintaining low contention
- Round-robin condvar signaling: blocking allocations cycle
through all shard condition variables to ensure fairness
- Blocks freed to allocator's shard: uses allocator_pid to
determine target shard, enabling natural load balancing as
process allocation patterns stabilize over time
Maintains existing robust mutex semantics including EOWNERDEAD
handling for dead process recovery. Internal structures exposed in
ssm.h for testing purposes. Adds some tests (pool_test,
pool_sharding_test.c. etc) verifying lazy distribution, migration,
fallback stealing, and multiprocess behavior.
Updates the ring buffer (rbuff) to use relaxed/acquire/release
ordering on atomic indices. The ring buffer requires the (robust)
mutex to ensure cross-structure synchronization between pool buffer
writes and ring buffer index publication.
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
| |
|
|
|
|
|
|
|
| |
This adds a BUILD_CONTAINER option that disables some features that
require elevated privileges like setting thread priorities, which
might not be supported in docker environments.
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
| |
|
|
|
|
|
| |
Slow but steady.
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
| |
|
|
|
|
|
| |
2022 was a rather slow year...
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
| |
|
|
|
|
|
| |
Growing pains.
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
Reading/writing to (N + 1)-flows from the IPCP was using a raw QoS flow
to bypass some functions in the ipcp_flow_read call. But this call was
broken for keepalive packets. Fixing the ipcp_flow_read call for
(N - 1) flows causes the IPCPs to drop 0-byte keepalive packets coming from
(N + 1) client flows.
>From now on, there is a dedicated call for (N + 1) reads/writes from
the IPCPs that's more efficient and cleaner. The (N + 1) flow internal
QoS is now also defaulted to a qos_np1 qosspec, instead of tampering
with the qosspec requested by the (N + 1) client.
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
| |
|
|
|
|
|
|
|
|
| |
The connection manager and enrolment components of the unicast and
broadcast IPCP have a lot in common, as conjectured in the paper. The
initial implementation of the broadcast IPCP just duplicated the
code. This moves the shared functionality to common ground.
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
| |
|
|
|
|
|
|
| |
The ugent email addresses are shut down, updated to Ouroboros mail
addresses.
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
| |
|
|
|
|
|
| |
Happy New Year, Ouroboros!
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
| |
|
|
|
|
|
|
| |
GCC 10 static analyzer found that the wrong index was used in the fail
path of psched_create, causing double (multiple) frees.
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
| |
|
|
|
| |
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
|
|
This completes the renaming of the normal IPCP to the unicast IPCP in
the sources, to get everything consistent with the documentation.
Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>
|
