Merge branch 'release/0.3.4'

Author: aramallo

CHANGELOG.md

@@ -1,4 +1,8 @@
 # CHANGELOG
+# 0.3.4
+* Makes io-uring an option disabled by default (AWS ECS crashes)
+* Reverts harcoded values in Cozo/cozorocks that where left during mem leak fix and allow them to be passed as ENV VARS. `option` is the main way to set those values, ENV VARS will override them
+
 # 0.3.3
 
 ## Bug Fixes
@@ -69,7 +73,7 @@
 * Added `COZODB_BACKEND` environment variable support in Makefile
   - `make build` or `make build-rocksdb` - Build with cozorocks (default)
   - `COZODB_BACKEND=newrocksdb make build` or `make build-newrocksdb` - Build with rust-rocksdb
-* Note: `rebar3_cargo` does not support passing Cargo features; use Makefile targets
+* Build options work with `make`, `rebar3 compile`, and `mix compile` via env vars
 
 ## Improvements
 * Improved Erlang serialization for better performance

Makefile

@@ -19,12 +19,33 @@ export JEMALLOC_SYS_WITH_MALLOC_CONF ?= background_thread:false,dirty_decay_ms:1
 # IMPORTANT: The two backends are MUTUALLY EXCLUSIVE due to allocator conflicts.
 COZODB_BACKEND ?= rocksdb
 
-# Cargo feature flags based on selected backend
+# io_uring for RocksDB async I/O (Linux-only, requires liburing-dev):
+#   COZODB_IO_URING=true  - Enable io_uring (bare-metal Linux recommended)
+#   COZODB_IO_URING=false - Disable io_uring (default, safe for containers)
+# WARNING: io_uring + jemalloc + RocksDB 10.9.1 crashes in container environments
+# (Docker named volumes, AWS ECS) due to TLS conflicts with the BEAM VM.
+COZODB_IO_URING ?= false
+
+# Cargo feature flags based on selected backend and options
+EXTRA_CARGO_FEATURES :=
+
+ifeq ($(COZODB_IO_URING),true)
+EXTRA_CARGO_FEATURES += io-uring
+endif
+
 ifeq ($(COZODB_BACKEND),newrocksdb)
+ifneq ($(EXTRA_CARGO_FEATURES),)
+CARGO_FEATURES := --no-default-features --features "new-rocksdb-default,$(EXTRA_CARGO_FEATURES)"
+else
 CARGO_FEATURES := --no-default-features --features "new-rocksdb-default"
+endif
+else
+ifneq ($(EXTRA_CARGO_FEATURES),)
+CARGO_FEATURES := --features "$(EXTRA_CARGO_FEATURES)"
 else
 CARGO_FEATURES :=
 endif
+endif
 
 .PHONY: all
 all: build
@@ -36,7 +57,7 @@ build: cargo-build
 # Build with the selected backend (controlled by COZODB_BACKEND env var)
 .PHONY: cargo-build
 cargo-build:
-	@echo "Building with COZODB_BACKEND=$(COZODB_BACKEND)"
+	@echo "Building with COZODB_BACKEND=$(COZODB_BACKEND) COZODB_IO_URING=$(COZODB_IO_URING)"
 	cd native/cozodb && cargo build --release $(CARGO_FEATURES)
 	@mkdir -p priv/crates/cozodb
 	@cp native/cozodb/target/release/libcozodb.so priv/crates/cozodb/cozodb.so 2>/dev/null || \

README.md

@@ -13,6 +13,8 @@ CozoDB is a FOSS embeddable, transactional, relational-graph-vector database, wi
 - [RocksDB Backends](#rocksdb-backends)
   - [rocksdb (cozorocks)](#1-rocksdb-cozorocks---default)
   - [newrocksdb (rust-rocksdb)](#2-newrocksdb-rust-rocksdb---alternative)
+- [Build Options](#build-options)
+  - [io_uring](#io_uring)
 - [Configuration](#configuration)
   - [jemalloc](#jemalloc)
   - [Docker](#docker)
@@ -30,8 +32,8 @@ CozoDB is a FOSS embeddable, transactional, relational-graph-vector database, wi
 {ok, Result} = cozodb:run(Db, "?[] <- [[1, 2, 3]]").
 
 %% Close the database
-%% Notice that close no longer releases the NIF resource. This will be done 
-%% when the Erlang GC triggers as long as you no longer have a reference to 
+%% Notice that close no longer releases the NIF resource. This will be done
+%% when the Erlang GC triggers as long as you no longer have a reference to
 %% `Db`.
 ok = cozodb:close(Db).
 ```
@@ -42,10 +44,11 @@ ok = cozodb:close(Db).
 
 | Platform | Dependencies |
 |----------|--------------|
-| **Runtime** | Erlang OTP26+ and/or Elixir (latest) |
-| **Build** | Rust 1.76.0+ |
+| **Runtime** | Erlang OTP27+ and/or Elixir (latest) |
+| **Build** | Rust 1.76.0+, Make |
 | **macOS** | `liblz4`, `libssl` |
-| **Linux** | `build-essential`, `liblz4-dev`, `libncurses-dev`, `libsnappy-dev`, `libssl-dev`, `liburing-dev`, `liburing2`, `pkg-config` |
+| **Linux** | `build-essential`, `liblz4-dev`, `libncurses-dev`, `libsnappy-dev`, `libssl-dev`, `pkg-config` |
+| **Linux (io_uring)** | All of the above plus `liburing-dev` (see [io_uring](#io_uring)) |
 
 ### Erlang
 
@@ -119,13 +122,7 @@ An alternative RocksDB backend using the official **rust-rocksdb** crate. This b
 
 #### Building with newrocksdb
 
-To use the `newrocksdb` backend, you must build with the `new-rocksdb-default` feature instead of the default features.
-
-> **Note:** The `rebar3_cargo` plugin does not support passing Cargo feature flags. Use the Makefile targets or manual Cargo build as described below.
-
-##### Option 1: Makefile with Environment Variable (Recommended)
-
-Use the provided Makefile with the `COZODB_BACKEND` environment variable:
+To use the `newrocksdb` backend, set the `COZODB_BACKEND` environment variable at compile time:
 
 ```bash
 # Use newrocksdb backend
@@ -140,40 +137,12 @@ make build
 make build-rocksdb
 ```
 
-##### Option 2: Manual Cargo Build
-
-Build the NIF manually before running rebar3:
+This works the same way when `cozodb` is used as a rebar3/mix dependency:
 
 ```bash
-# In native/cozodb directory
-cargo build --release --no-default-features --features "new-rocksdb-default"
-
-# Copy the built library to priv/
-mkdir -p ../../priv/crates/cozodb
-cp target/release/libcozodb.dylib ../../priv/crates/cozodb/cozodb.so  # macOS
-# or: cp target/release/libcozodb.so ../../priv/crates/cozodb/cozodb.so  # Linux
-
-# Then compile Erlang code only
-cd ../..
-rebar3 compile
+COZODB_BACKEND=newrocksdb rebar3 compile
 ```
 
-##### Option 3: Modify Cargo.toml
-
-Edit `native/cozodb/Cargo.toml` to change the default features permanently:
-
-```toml
-[features]
-default = [
-    "cozo/storage-sqlite",
-    "cozo/storage-new-rocksdb",  # Changed from storage-rocksdb
-    "cozo/graph-algo",
-    "jemalloc"
-]
-```
-
-Then build normally with `make build` or `rebar3 compile`.
-
 #### newrocksdb Environment Variables
 
 The `newrocksdb` backend reads configuration from `COZO_ROCKSDB_*` environment variables:
@@ -263,6 +232,36 @@ os:putenv("COZO_ROCKSDB_ENABLE_STATISTICS", "true"),
 {ok, Db} = cozodb:open(newrocksdb, "/path/to/db").
 ```
 
+## Build Options
+
+All build options are controlled via environment variables and work with `make build`, `rebar3 compile`, and `mix compile`:
+
+| Variable | Values | Default | Description |
+|----------|--------|---------|-------------|
+| `COZODB_BACKEND` | `rocksdb`, `newrocksdb` | `rocksdb` | RocksDB backend selection |
+| `COZODB_IO_URING` | `true`, `false` | `false` | Enable Linux io_uring async I/O |
+
+### io_uring
+
+Linux io_uring support for RocksDB async I/O is available as an opt-in build feature. It is **disabled by default** because the combination of io_uring + jemalloc + RocksDB 10.9.1 causes segfaults in container environments (Docker with named volumes, AWS ECS). This is due to TLS (Thread Local Storage) conflicts between RocksDB's per-thread io_uring instances, jemalloc's thread caches, and the BEAM VM's dirty IO scheduler threads.
+
+When disabled, RocksDB uses standard `pread`/`pwrite` syscalls which perform well across all environments.
+
+To enable io_uring (Linux-only, requires `liburing-dev`):
+
+```bash
+# Direct build
+COZODB_IO_URING=true make build
+
+# As a rebar3 dep
+COZODB_IO_URING=true rebar3 compile
+
+# Docker
+docker build --build-arg COZODB_IO_URING=true -t myapp .
+```
+
+> **WARNING:** Only enable io_uring for bare-metal Linux deployments where you have verified it works with your kernel version. Do not enable in container environments (Docker, ECS, Kubernetes).
+
 ## Configuration
 
 ### jemalloc
@@ -320,6 +319,14 @@ For container compatibility, set `JEMALLOC_SYS_WITH_MALLOC_CONF` to bake safe de
 ENV JEMALLOC_SYS_WITH_MALLOC_CONF="background_thread:false,dirty_decay_ms:1000,muzzy_decay_ms:1000"
 ```
 
+#### io_uring in Docker
+
+io_uring is disabled by default, which is the recommended setting for container deployments. If you need to enable it (not recommended), pass the build arg:
+
+```bash
+docker build --build-arg COZODB_IO_URING=true -t myapp .
+```
+
 ### Memory Tuning Tips
 
 | Use Case | Recommendation |
@@ -330,39 +337,33 @@ ENV JEMALLOC_SYS_WITH_MALLOC_CONF="background_thread:false,dirty_decay_ms:1000,m
 
 ## Development
 
-### Upgrading the cozo Dependency
+### Building
 
 ```bash
-cd native/cozodb
-cargo update -p cozo
-```
-
-### Using newrocksdb Backend as a Consumer
-
-By default, cozodb compiles with the `rocksdb` (cozorocks) backend. If you need the `newrocksdb` backend with environment variable configuration in your own project, you have two options:
+# Default build (rocksdb backend, no io_uring)
+make build
 
-#### Option A: Fork and Modify (Recommended)
+# With newrocksdb backend
+COZODB_BACKEND=newrocksdb make build
 
-1. Fork the cozodb repository
-2. Modify `native/cozodb/Cargo.toml` to use `new-rocksdb-default` as the default features
-3. Point your dependency to your fork
+# With io_uring (Linux bare-metal only)
+COZODB_IO_URING=true make build
 
-#### Option B: Pre-build the NIF
+# Combine options
+COZODB_BACKEND=newrocksdb COZODB_IO_URING=true make build
+```
 
-Before running `rebar3 compile` in your project:
+### Running Tests
 
 ```bash
-# Clone cozodb
-git clone https://github.com/leapsight/cozodb.git /tmp/cozodb
-cd /tmp/cozodb
+make test
+```
 
-# Build with newrocksdb backend
-COZODB_BACKEND=newrocksdb make cargo-build
+### Upgrading the cozo Dependency
 
-# Copy the built NIF to your project's _build directory
-# (after rebar3 has fetched dependencies)
-mkdir -p YOUR_PROJECT/_build/default/lib/cozodb/priv/crates/cozodb
-cp priv/crates/cozodb/cozodb.so YOUR_PROJECT/_build/default/lib/cozodb/priv/crates/cozodb/
+```bash
+cd native/cozodb
+cargo update -p cozo
 ```
 
 ## License

benchmark/Dockerfile

@@ -3,6 +3,10 @@
 
 FROM elixir:1.18-otp-27
 
+# Build args for compile-time feature selection
+# Set COZODB_IO_URING=true to enable io_uring (not recommended for containers)
+ARG COZODB_IO_URING=false
+
 # Install build dependencies
 RUN apt-get update && apt-get install -y \
     build-essential \
@@ -12,10 +16,14 @@ RUN apt-get update && apt-get install -y \
     clang \
     libclang-dev \
     pkg-config \
-    liburing-dev \
     procps \
     && rm -rf /var/lib/apt/lists/*
 
+# Conditionally install liburing-dev when io_uring is enabled
+RUN if [ "$COZODB_IO_URING" = "true" ]; then \
+        apt-get update && apt-get install -y liburing-dev && rm -rf /var/lib/apt/lists/*; \
+    fi
+
 # Install Rust
 RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
 ENV PATH="/root/.cargo/bin:${PATH}"
@@ -39,8 +47,7 @@ ENV JEMALLOC_SYS_WITH_MALLOC_CONF="background_thread:false,dirty_decay_ms:1000,m
 # Different from macOS Apple Silicon which uses 16KB (LG_PAGE=14) or 64KB pages
 ENV JEMALLOC_SYS_WITH_LG_PAGE=12
 
-
-RUN cd native/cozodb && cargo build --release
+RUN COZODB_IO_URING=${COZODB_IO_URING} make cargo-build
 
 # Copy the built NIF to priv directory
 RUN mkdir -p priv/crates/cozodb && \

native/cozodb/Cargo.toml

@@ -2,7 +2,7 @@
 name = "erlang-cozodb"
 description = "Erlang NIF wrapper for CozoDB using Rustler."
 authors = ["Alejandro M. Ramallo"]
-version = "0.3.3"
+version = "0.3.4"
 edition = "2021"
 
 [lib]
@@ -13,7 +13,7 @@ crate-type = ["cdylib"]
 [dependencies]
 rustler = {version = "=0.37.0", features = ["nif_version_2_17"]}
 # Using local path temporarily to test new memory stats functionality
-cozo = {git = "https://github.com/aramallo/cozo.git", tag = "v0.8.2-leapsight" }
+cozo = {git = "https://github.com/aramallo/cozo.git", tag = "v0.8.3-leapsight" }
 uuid = "1.3.3"
 threadpool = "1.8.1"
 once_cell = "1.21.3"
@@ -105,6 +105,13 @@ nif_alloc_rocksdb_jemalloc = ["nif_alloc", "tikv-jemalloc-ctl", "tikv-jemalloc-s
 # Requires: MALLOC_CONF="prof:true" at runtime to activate.
 jemalloc-profiling = ["tikv-jemallocator/profiling", "tikv-jemalloc-ctl/profiling", "tikv-jemalloc-sys/profiling"]
 
-[target.'cfg(target_os = "linux")'.dependencies]
-cozo = { git = "https://github.com/aramallo/cozo.git", tag = "v0.8.2-leapsight", features = ["io-uring"] }
+# Enable Linux io_uring for RocksDB async I/O (Linux-only, requires liburing-dev).
+# Disabled by default due to crashes when combined with jemalloc on RocksDB 10.9.1
+# in container environments (Docker named volumes, AWS ECS).
+# The issue is a three-way interaction between RocksDB 10.9.1's per-thread
+# io_uring instances (ThreadLocalPtr/pthread TLS), jemalloc's TLS-based thread
+# caches, and the BEAM VM's many dirty IO scheduler threads.
+# RocksDB falls back to standard pread/pwrite which performs well.
+# Enable via: COZODB_IO_URING=true make build
+io-uring = ["cozo/io-uring"]