MariaDB

Author: Ludovic HENRY <ludovic.henry@qti.qualcomm.com> Date: 2026-06-17 Scope: RISC-V (riscv64/linux) support status for MariaDB Audience: Technical leadership, resource allocation strategy Verification policy: Every claim is cross-referenced to a primary upstream source. Items that could not be verified against a second source are marked [NEEDS VERIFICATION].

1. Project Overview

MariaDB Server is a GPLv2-licensed relational database management system (RDBMS) forked from MySQL 5.5 in 2010 by Michael Widenius. It includes multiple pluggable storage engines (InnoDB, MyRocks/RocksDB, Aria, Spider, S3), a built-in query optimizer, and a full SQL/procedural language stack. The server is written in C and C++ with targeted assembly for performance-critical subsystems.

Governance. MariaDB is controlled by the MariaDB Foundation, a non-profit Delaware corporation. The Foundation holds legal control but has no technical veto authority. Technical decisions are made by open consensus on the maria-developers mailing list. The project uses JIRA (MDEV) for issue tracking and GitHub for code hosting and PR review. New architecture ports do not require a governance vote or a formal RFC; the bar is technical merit reviewed by Foundation staff. Contributions are accepted under the MariaDB Contributor Agreement (MCA), BSD-new, or public domain.

Corporate sponsors. As of August 2024 (CREDITS file in the repository):

Tier Members
Diamond Amazon, DBS Bank
Platinum IBM, Intel, MariaDB Corporation
Gold Hetzner, IONOS, Scarf
Silver Automattic, Wikimedia Foundation, Nextcloud, Tencent Cloud, Percona, ServiceNow, Alibaba Cloud, and approximately 25 others

Community stance on new ports. The pattern of RISC-V fixes being accepted from IBM employees (Daniel Black), community contributors affiliated with lowRISC (alexfanqi), and OpenBSD developers (Brad Smith) confirms an open, pragmatic stance. No RISC-V maintainer objections appear in any JIRA comment or PR review thread found in the research.

RISE involvement. MariaDB is not a RISE Project member and has received no RISE funding. All 27 RISE blog posts from May 2024 through June 2026 were checked; none mentions MariaDB.

2. Port History and Upstreaming Timeline

All fixes are upstream in the main repository at MariaDB/server. There is no out-of-tree riscv64 patch set.

Date Event Source
2020-07-02 First RISC-V commit: MDEV-23051, RocksDB build fails on riscv64 due to missing -latomic linkage. Merged 2020-07-28. Fixed in 10.2.33, 10.3.24, 10.4.14, 10.5.5. PR #1617
2020-12-21 MDEV-24456 filed: main.join_outer and main.join_outer_jcl6 tests time out after 900 seconds on riscv64. Open, unassigned. JIRA
2021-12-20 Fix riscv64 build failure linking correctly with pthread (commit cc3105e). GitHub
2022-01-04 MDEV-27429: Add rdtime CSR support for RISC-V cycle timer. Contributor: alexfanqi (community, lowRISC-adjacent). Fixed in 10.8.0. GitHub commit d18f6f2
2022-03-18 Enable pmem (persistent memory) on riscv64 in Debian packaging. GitHub commit 63f76d3
2022-10-26 MDEV-29875 filed: RocksDB (MyRocks) fails to build on riscv64 due to stale bundled submodule and jemalloc mm_malloc.h scope issue. Open, critical. JIRA
2023-02-03 MDEV-30554: Re-fix RocksDB libatomic linking regression on riscv64 (regression of MDEV-23051). Fixed in 10.4.29-11.0.1. GitHub commit 17423c6
2023-03-18 MDEV-33750: Enable mariadb-plugin-rocksdb for riscv64 in Debian packaging. Fixed in packaging. GitHub commit 9e92112
2024-08-28 MDEV-34825: FreeBSD riscv64 compatibility patch. Fixed in 10.5.27, 10.6.20, 11.4.4. Contributor: Brad Smith (OpenBSD/community). GitHub commit e9b70e5
2024-11-25 MDEV-34815: SIGILL on riscv64 when compiled with Clang 17. rdcycle is privileged in Linux kernel 6.6+; fix uses rdtime instead. Fixed in 10.11.11, 11.4.5, 11.7.2. Contributor: Daniel Black (MariaDB Foundation). GitHub commit aca72b3
2025-01-13 MDEV-35827: Replace expensive generic MY_RELAX_CPU spin-wait with __builtin_riscv_pause() on RISC-V. Contributor: Marko Makela (MariaDB Corporation, InnoDB lead). PR #3752
2025-02 MDEV-36217: Build regression from MDEV-35827 on Ubuntu 22.04/24.04 (compiler/assembler too old for __builtin_riscv_pause). Switched to raw opcode .long 0x0100000f. Fixed in 10.6.22, 10.11.12, 11.4.6, 11.8.2. JIRA
2025-03-07 Fix building with both Clang and GCC on RISC-V (compiler guard for GCC-only intrinsic). Contributor: Brad Smith. GitHub commit 05be186
2026-03-25 MDEV-39142: InnoDB fails to start on sv39 kernels (512 GiB VA limit). InnoDB default innodb_buffer_pool_size_max=8TiB requires 43-bit VA; fix retries mmap with 128 GiB. Merged 2026-03-25. Contributor: Marko Makela. PR #4852

Key contributors and affiliations:

GitHub login Name Affiliation Primary riscv64 contributions
grooverdan Daniel Black MariaDB Foundation (daniel@mariadb.org; previously IBM/daniel@linux.ibm.com) MDEV-23051 (atomics), MDEV-34815 (SIGILL/Clang fix)
dr-m Marko Makela MariaDB Corporation (InnoDB lead) MDEV-35827 (MY_RELAX_CPU), MDEV-39142 (InnoDB VA bits)
alexfanqi – Community (alex.fan.q@gmail.com; lowRISC-adjacent) MDEV-27429 (rdtime timer)
bradsmith Brad Smith Community/OpenBSD (brad@comstyle.com) MDEV-34825 (FreeBSD), MDEV-29875 reporter, toolchain fixes

The riscv64 port is fully upstream with no out-of-tree patches required. IBM drove initial enablement (2020); subsequent work has come from MariaDB Corporation staff and community contributors.

3. Upstream Support Tier

MariaDB has no published platform support tier document (no PLATFORMS.md, SUPPORTED.md, or equivalent in the repository). Support tiers are inferred from CI, release blocking, and packaging evidence.

Criteria amd64 arm64 riscv64
Listed in CI matrix Yes (all CI) No (not in GitLab CI) No
Official riscv64 binaries on mariadb.org Yes Yes (tarballs) No
Debian official build Yes (primary) Yes Yes (ports, autopkgtest Pass)
Ubuntu official package Yes Yes Yes (via ports repository)
Docker Hub official image Yes Yes (arm64v8) No
Debian packaging Architecture field any (implicit) any (implicit) any (implicit); RocksDB plugin: explicit riscv64 listed
Build blocks releases Yes Not verifiable No
Known open correctness bugs None found None found MDEV-24456 (test timeouts), MDEV-29875 (RocksDB build)

Assessment: riscv64 is an implicit community-supported architecture. It is not a release-blocking tier. Debian and Ubuntu maintainers independently build and ship packages from source, and those packages currently pass autopkgtests. MariaDB’s own engineering org performs no riscv64 validation before releasing.

The Debian debian/control file in the repository explicitly lists riscv64 in the Architecture: field of the mariadb-plugin-rocksdb package alongside amd64 arm64 mips64el ppc64el, which is the strongest signal of intentional riscv64 support commitment from the MariaDB project itself.

4. Technical Architecture and RISC-V-Specific Subsystems

MariaDB has no JIT query compiler. Architecture-specific code is limited to performance-oriented subsystems: CPU synchronization primitives, hardware timers, checksum acceleration, and InnoDB memory management.

Component inventory

include/my_cpu.h – CPU spin-wait / yield hint

Used in lock contention loops (LF_BACKOFF, ut_delay). RISC-V implementation (post MDEV-36217, currently in 10.6.22+, 10.11.12+, 11.4.6+, 11.8.2+):

#elif defined __GNUC__ && defined __riscv
  __asm__ volatile(".long 0x0100000f" ::: "memory");

The opcode 0x0100000f is the Zihintpause pause instruction encoding. Per the spec, on cores that do not implement Zihintpause, this decodes as a fence variant and acts as a memory barrier – no SIGILL. Works with any GCC that supports inline asm and the __riscv predefined macro (GCC 7+).

include/my_rdtsc.h – hardware cycle/time counter

Used for profiling and timing infrastructure. RISC-V implementation (added MDEV-27429, Jan 2022):

  • riscv64: __asm __volatile("rdtime %0" : "=r"(result)) - reads the time CSR
  • riscv32: three-step rdtimeh/rdtime/rdtimeh sequence to handle 64-bit rollover across two 32-bit reads
  • Named constant MY_TIMER_ROUTINE_RISCV = 30

rdtime is a Zicsr pseudo-instruction present in all RV32/RV64 implementations and accessible from user mode. This is correct. rdcycle (previously used via Clang’s __builtin_readcyclecounter) became a privileged instruction in Linux kernel 6.6 and caused SIGILL until MDEV-34815 (Nov 2024).

storage/innobase/sync/cache.cc – InnoDB pmem cache flush

RISC-V implementation:

// riscv64 path
__asm__ volatile("fence w,w" ::: "memory");

Compared to aarch64 (dc cvac/cvap + dmb ishst, per-cacheline) and x86 (clflush/clflushopt/clwb + sfence, per-cacheline). RISC-V lacks a per-cacheline flush instruction in the base ISA; the fence w,w is functionally correct for ordering but does not flush cachelines to persistent media. This is an ISA limitation, not a MariaDB gap.

mysys/crc32/crc32c.cc and mysys/crc32/ – CRC32 and CRC32c

Architecture Implementation File
x86_64 SSE4.2 hardware CRC crc32_x86.c
aarch64 ACLE intrinsics, hardware CRC crc32_arm64.c
ppc64 POWER8 VSX crc32_ppc64.c
riscv64 crc32c_slow() software LUT (generic fallback)

No crc32_riscv64.c exists in the repository. riscv64 uses the generic software table-based CRC computation for all CRC operations. The RISC-V Zbc extension (carry-less multiply instructions, clmul/clmulh/clmulr) would enable hardware-accelerated CRC, but no MariaDB implementation exists. This is the most significant measurable performance gap for riscv64.

storage/innobase/sync/srw_lock.cc – InnoDB shared/exclusive lock

x86 has a hardware RTM (Restricted Transactional Memory) path. ppc64 has a __TM_* HTM path. riscv64 falls through to the generic SUX_LOCK_GENERIC pthread mutex path. aarch64 also uses the generic pthread path in this file, so this is not exclusively a riscv64 deficit.

Atomics (include/atomic/gcc_builtins.h)

All architectures use GCC C11 __atomic_* builtins. This is an intentional design decision; there are no x86 or arm64 specialized atomic files. On riscv64, sub-word (1- and 2-byte) atomics require linking with -latomic because older GCC toolchains do not inline them – this is the root cause of MDEV-23051 and MDEV-30554.

Summary table

Component amd64 arm64 riscv64 riscv64 status
JIT query compiler None None None N/A (MariaDB has no JIT)
CPU relax / pause hint PAUSE instruction GCC memory clobber asm (generic) .long 0x0100000f (Zihintpause encoding) Complete
Cycle/time counter __rdtsc() mrs CNTVCT_EL0 rdtime %0 (Zicsr) Complete
CRC32c SSE4.2 hardware ACLE hardware crc32c_slow() software LUT Performance gap (no Zbc path)
CRC32 ISO PCLMULQDQ SIMD ACLE hardware Generic C fallback Performance gap
InnoDB pmem cache flush clflush/clwb per-cacheline dc cvac/cvap per-cacheline fence w,w (no per-cacheline flush) ISA limitation
InnoDB SRW lock RTM hardware path pthread generic pthread generic Same as arm64
Atomics (all widths) GCC __atomic_* GCC __atomic_* GCC __atomic_* + -latomic required Complete (requires explicit library link)
InnoDB buffer pool VA sizing 47-bit assumed 39-bit minimum (MDEV-39142) 39-bit minimum (sv39, MDEV-39142) Complete (fixed Mar 2026)

5. Build System, Cross-Compilation, and Toolchain

Native build (on riscv64 host) 

mkdir build && cd build
cmake .. -DCMAKE_BUILD_TYPE=RelWithDebInfo \
         -DPLUGIN_ROCKSDB=NO
make -j$(nproc)

-DPLUGIN_ROCKSDB=NO is required; the RocksDB plugin does not build cleanly on riscv64 (MDEV-29875, open since 2022).

Cross-compilation (two-stage)

MariaDB generates host-side tools during the build that must execute on the build machine. Cross-compilation requires a two-stage process:

# Stage 1: build host helper tools
mkdir host && cd host
cmake ..
make import_executables
cd ..

# Stage 2: cross-compile for riscv64 target
mkdir target && cd target
cmake .. \
  -DCMAKE_TOOLCHAIN_FILE=/path/to/riscv64-toolchain.cmake \
  -DIMPORT_EXECUTABLES=../host/import_executables.cmake
make

A minimum toolchain cmake file must set values that cannot be detected at cross-compile time:

SET(CMAKE_SYSTEM_NAME Linux)
SET(CMAKE_SYSTEM_PROCESSOR riscv64)
SET(CMAKE_C_COMPILER riscv64-linux-gnu-gcc)
SET(CMAKE_CXX_COMPILER riscv64-linux-gnu-g++)
SET(STACK_DIRECTION -1)
SET(HAVE_IB_GCC_ATOMIC_BUILTINS 1)

No MariaDB-provided toolchain cmake file for riscv64 exists in the repository. The files cmake/riscv64.cmake and cmake/toolchain-riscv64.cmake do not exist (verified as 404).

Toolchain version requirements

GCC: The current source (post MDEV-36217) uses raw opcode .long 0x0100000f instead of __builtin_riscv_pause(). This works with any GCC supporting inline asm and the __riscv predefined macro (GCC 7+). Ubuntu 22.04 GCC 11 is confirmed to work with current MariaDB versions.

Clang: Clang 17 or earlier with riscv64 target requires MariaDB 10.11.11+, 11.4.5+, or 11.7.2+ to avoid the MDEV-34815 SIGILL. Earlier MariaDB releases compiled with Clang on riscv64 will crash at runtime when my_timer_cycles() executes rdcycle, which is a privileged instruction under Linux kernel 6.6+.

libatomic: Must be linked explicitly when building RocksDB or any component using sub-word atomic operations on riscv64. This is handled by MariaDB’s cmake since MDEV-23051 and MDEV-30554. No manual override needed for current releases.

QEMU usage

No QEMU usage appears in any MariaDB CI configuration or build documentation. MDEV-24456 shows test suite timeouts on riscv64 (likely under QEMU emulation), but no documented procedure for QEMU-based testing exists in the repository.

InnoDB pmem (WITH_INNODB_PMEM)

The cmake logic in storage/innobase/CMakeLists.txt explicitly matches riscv64 in the regex pattern (aarch|AARCH|p(ower)?pc|x86_|amd|loongarch|riscv)64, setting WITH_INNODB_PMEM=ON by default on riscv64. No manual override is required.

6. Feature Coverage and Gap Analysis vs arm64 and amd64

Functional gaps

Feature amd64 arm64 riscv64 Impact
RocksDB (MyRocks) storage engine Supported Supported Not buildable from default bundled submodule (MDEV-29875) High: MyRocks is MariaDB’s primary LSM-tree storage engine; riscv64 deployments requiring it must patch manually
Docker official image Available Available (arm64v8) Not available Medium: riscv64 users must build from source or use distro packages
Official binary tarball (mariadb.org) Available Available Not available Low: distro packages available as substitute
InnoDB buffer pool full default (8TiB) Supported (47-bit VA) Supported Limited to 128 GiB on sv39 kernels Low: MariaDB falls back automatically (MDEV-39142, fixed Mar 2026); operator can set innodb_buffer_pool_size_max explicitly

Performance gaps

Subsystem amd64 arm64 riscv64 Estimated impact
CRC32c (InnoDB page checksums, binlog, replication) Hardware SSE4.2 Hardware ACLE Software LUT Data not available: no published benchmark figures for riscv64 vs amd64 MariaDB CRC performance
CRC32 ISO (protocol-level checksums) PCLMULQDQ SIMD Hardware ACLE Generic C Data not available: same caveat
Spin-wait efficiency PAUSE instruction Generic GCC asm Zihintpause (.long 0x0100000f) Minimal: RISC-V hardware yields correctly; not a bottleneck under normal load
SRW lock (InnoDB high-concurrency) RTM hardware path (when TSX available) pthread generic pthread generic Moderate under high write concurrency; same as arm64

Security hardening

Data not available: no search results found comparing -fstack-protector, CFI, shadow call stack, or PAC/BTI coverage between amd64, arm64, and riscv64 in the MariaDB build system.

Floating-point and numeric semantics

MariaDB uses IEEE 754 double-precision for DOUBLE columns and DECIMAL for exact arithmetic. riscv64 uses the standard F/D extensions for hardware floating-point, which are IEEE 754 compliant. No RISC-V-specific floating-point issues appear in JIRA.

7. CI/CD Infrastructure

The riscv64 CI situation has been verified by reading the actual CI configuration files in the repository:

CI system File riscv64 present
GitHub Actions .github/workflows/windows-arm64.yml No; Windows ARM64 only
GitHub Actions .github/workflows/backup.yml No; ubuntu-latest (x86) only
GitHub Actions .github/workflows/label_recent_prs.yaml No; ubuntu-latest (x86) only
GitLab CI .gitlab-ci.yml No; Fedora/CentOS/Amazon Linux amd64 only
Debian Salsa CI debian/salsa-ci.yml No; amd64 only
Buildbot buildbot.mariadb.org No; 1,255+ builders, none for riscv64
Jenkinsfile Not present (404) N/A
Cirrus CI Not present (404) N/A

Conclusion: MariaDB has zero riscv64 CI of any kind. The only non-x86 CI target is Windows ARM64 (one GitHub Actions workflow for native ARM64 Windows builds). All riscv64 validation is performed externally by Debian and Ubuntu maintainers as part of their distribution build infrastructure.

Criteria amd64 arm64 riscv64
Upstream CI coverage Full (GitLab CI, GitHub Actions, Buildbot) None None
Release-blocking CI Yes No No
RISE CI runners N/A N/A None
External distro CI Debian, Ubuntu, Arch Debian, Ubuntu Debian (autopkgtest Pass), Arch RISC-V

8. Distribution and Release Status

Official channels

  • mariadb.org binary tarballs: x86_64 only. No riscv64 tarballs offered.
  • GitHub releases: No binary assets attached to any release for any architecture. MariaDB does not distribute binaries via GitHub releases.
  • Docker Hub official image (docker.io/mariadb): Supported architectures are amd64, arm64/v8, ppc64le, s390x. riscv64 is absent. The .architectures-lib configuration hardcodes the supported set.
  • MariaDB Python connector (mariadb on PyPI, version 1.1.14): Windows wheels (win32, win_amd64 for cp39-cp314) and source distributions only. No riscv64 wheel.

Community distribution packages

Distribution Version riscv64 status Notes
Debian sid 1:11.8.8-1 Available, autopkgtest Pass All ~64 packages including mariadb-plugin-rocksdb. Migration to testing blocked by unrelated rtpengine regression.
Debian trixie 11.8.6 Available In testing
Ubuntu Noble (24.04) 10.11.x Available (ports) Via ports.ubuntu.com/ubuntu-ports; approximately 33 packages including RocksDB plugin
Ubuntu Questing/Resolute/Stonking 11.8.x Available (ports) Via Ubuntu ports repository
Arch Linux RISC-V (archriscv.felixc.at) 12.3.2-2, 11.8.8-1 Available Current and LTS; mariadb-12.3.2-2-riscv64.pkg.tar.zst (38 MB), built 2026-06-08; also mariadb-lts-11.8.8-1-riscv64.pkg.tar.zst (34 MB)

What a user must do to get a working binary on riscv64: Install from Debian sid, Ubuntu ports, or Arch RISC-V package manager. No action by the MariaDB project is required. RocksDB (MyRocks) will be present in the Debian package but may have limitations due to the stale submodule issue (MDEV-29875).

9. Dependencies

Summary table

Dependency Role riscv64 build riscv64 test riscv64 release Blockers
OpenSSL TLS/crypto for connections and certificates Builds (generic C; linux64-riscv64 target exists but inherits only linux-generic64) No dedicated CI Packaged (Debian/Ubuntu riscv64) No assembly crypto optimizations for riscv64 yet; AES-GCM, ChaCha20, Poly1305 PRs open upstream
zlib Row/InnoDB compression; network compression Builds (pure C) No riscv64 failures reported All major distros No blockers
PCRE2 SQL REGEXP engine (system or bundled 10.47) Builds JIT backend functional (SLJIT has sljitNativeRISCV_64.c); one resolved JIT issue (pcre2#831, closed Oct 2025) Packaged (Debian/Ubuntu riscv64) No current blockers
libnuma InnoDB NUMA-interleave memory allocation Builds NUMA topology detection works on riscv64 Linux Packaged No blockers
readline / libedit mysql/mariadbd client interactive editing Builds (pure C) No riscv64 issues Packaged No blockers
libsystemd Socket activation, journal logging Builds (pure C) No riscv64 issues Packaged No blockers
RocksDB (bundled submodule) MyRocks storage engine (LSM-tree) Not cleanly buildable (MDEV-29875, open critical) Partial Not officially released for riscv64 MDEV-29875 (critical, open); upstream RocksDB PRs #14485 and #14530 open but unmerged as of Jun 2026
libatomic Atomic ops fallback for sub-word atomics on riscv64 Required, explicitly linked since MDEV-23051 Builds when linked Available in all distros as libatomic1 No current blockers
Boost.Context Optional Connector/C async protocol Builds (riscv64 backend since Boost 1.77) Not tested Available in distros No blockers

OpenSSL deep-dive

OpenSSL’s linux64-riscv64 target inherits from linux-generic64 and compiles the generic C implementation of all cipher and hash primitives. Hardware-accelerated AES-GCM, ChaCha20-Poly1305, and SHA implementations using the RISC-V Vector extension (RVV) and RISC-V Cryptography extensions are the subject of open upstream PRs in the OpenSSL repository (openssl/openssl #30787, #31182, #30552). These PRs were not merged as of the research date. The impact on MariaDB is a performance gap in TLS-intensive workloads on riscv64. No functional impact. See project-reports/openssl.md for full details.

PCRE2 / SLJIT deep-dive

The SLJIT JIT backend for RISC-V (sljitNativeRISCV_64.c) is present in the PCRE2 source. One issue was resolved in October 2025 (pcre2#831: JIT was broken with -march=rv64gcb_zicond due to march flag conflicts). No current blockers for MariaDB’s use of PCRE2 on riscv64. See project-reports/pcre2.md for full details.

RocksDB deep-dive (critical dependency)

The MyRocks storage engine bundles RocksDB as a git submodule. The riscv64 situation:

  1. MDEV-23051 (fixed 2020): Missing -latomic linkage. Root cause: riscv64 GCC does not inline sub-word atomic operations; libatomic must be linked explicitly. Fixed in cmake.

  2. MDEV-30554 (regression, fixed 2023): The same -latomic fix was lost when cmake logic was copied for a new build target. Re-fixed in 10.4.29-11.0.1.

  3. MDEV-29875 (open, critical, last updated 2026-06-02): The bundled RocksDB submodule has not been updated to include upstream commits required for riscv64. Specifically, the jemalloc_helper mm_malloc.h scope fix (upstream RocksDB commit bac39944) must be applied. Upstream RocksDB PRs #14485 and #14530 were open but not merged as of research date. The submodule update effort (MDEV-16523) improved the situation by moving to RocksDB 6.29, but the issue remains open. Brad Smith notes [NEEDS VERIFICATION] that rolling to 6.29 “helped eliminate most of the patching.”

Practical consequence: Users requiring MyRocks on riscv64 must apply manual patches to the bundled submodule or use a distro-provided package that includes those patches. The Debian mariadb-plugin-rocksdb package for riscv64 is explicitly listed in debian/control and ships in Debian sid, suggesting Debian maintainers have resolved the build issues in their packaging pipeline, but the upstream MariaDB repository does not build RocksDB cleanly for riscv64 without workarounds.

11. Known Bugs and Active Issues

Open issues

ID Title Severity Status Notes
MDEV-29875 RocksDB (MyRocks) fails to build on riscv64 from bundled submodule Critical Open (last updated 2026-06-02) Upstream RocksDB PRs #14485, #14530 open; Debian packages work but upstream source does not build cleanly. No fix version set.
MDEV-24456 main.join_outer and main.join_outer_jcl6 tests timeout after 900s on riscv64 Minor Open (since 2020-12-21, last updated 2025-06-12) Unassigned, no fix version set. Likely QEMU speed or a timeout threshold not calibrated for slow architectures. Not a correctness bug.

Recently fixed issues (closed, no longer blocking)

ID Title Fixed in Fixed date
MDEV-23051 RocksDB build fails: missing -latomic 10.2.33, 10.3.24, 10.4.14, 10.5.5 Jul 2020
MDEV-27429 Add RISC-V rdtime cycle timer support 10.8.0 Jan 2022
MDEV-30554 RocksDB libatomic linking regression on riscv64 10.4.29-11.0.1 Feb 2023
MDEV-33435 RISC-V RDCYCLE userland access broken in kernel 6.6+ 10.11.8, 11.0.6-11.4.2 2024
MDEV-34815 SIGILL on riscv64 compiled with Clang (rdcycle is privileged) 10.11.11, 11.4.5, 11.7.2 Dec 2024
MDEV-35827 Expensive generic MY_RELAX_CPU; riscv64 now uses Zihintpause 10.6+, 11.4+ Jan 2025
MDEV-36217 Build regression from MDEV-35827 on Ubuntu 22.04/24.04 toolchains 10.6.22, 10.11.12, 11.4.6, 11.8.2 Feb 2025
MDEV-39142 InnoDB fails to start on sv39 RISC-V kernels (512 GiB VA limit) Pending (merged Mar 2026) Mar 2026

Correctness note on MDEV-39142

This is the most operationally significant recent fix. All production RISC-V Linux systems use sv39 (39-bit virtual address space, 512 GiB maximum). InnoDB’s default innodb_buffer_pool_size_max=8TiB requires 43-bit VA and failed with an unrecoverable error on sv39 at startup. Without the MDEV-39142 fix, InnoDB could not start at all on any RISC-V Linux deployment using a default configuration. The fix, merged 2026-03-25, retries the mmap with 128 GiB on first failure, which fits within sv39. Release targeting is pending as of the research date.

12. Objections and Upstream Blockers

No stated objections to riscv64 support appear in any JIRA comment or PR review thread found in the research. The project has consistently accepted riscv64 contributions from external contributors.

Technical blockers:

  1. MDEV-29875 (open, critical): RocksDB (MyRocks) does not build from the default bundled submodule on riscv64. Unblocked when upstream RocksDB PRs #14485 and #14530 are merged and the MariaDB submodule is updated. No committed timeline.

  2. MDEV-39142 not yet in a stable release: The InnoDB sv39 fix is merged but not yet tagged into a numbered release. Any riscv64 deployment using InnoDB (the default storage engine) needs either the Debian sid package (which includes the fix) or to build from a post-March-2026 main branch commit.

  3. OpenSSL riscv64 crypto performance: No hardware-accelerated AES/ChaCha20/SHA in the OpenSSL version shipped with current Linux distributions for riscv64. Multiple upstream PRs are open. This is an OpenSSL project concern, not a MariaDB-specific blocker, but it degrades TLS throughput for any MariaDB deployment requiring encryption-at-transit.

  4. No riscv64 CI: MariaDB can ship riscv64 regressions silently. MDEV-35827/MDEV-36217 demonstrated this: the Jan 2025 MY_RELAX_CPU fix introduced a build regression on Ubuntu 22.04 and 24.04 riscv64 toolchains within weeks. Without CI, regression detection depends on Debian/Ubuntu maintainers filing bugs after package builds fail. The latency from regression introduction to fix release was approximately 1 month in that case.

Acceptance probability for contributions: High. The project has accepted riscv64 contributions from IBM, community developers, and OpenBSD developers with no stated friction. The contribution process requires a JIRA MDEV entry and a GitHub PR; no governance vote is required for architecture support changes.

13. Investment Analysis

RISE has not funded any MariaDB work. All riscv64 work to date has been contributed by IBM (initial port), MariaDB Corporation staff (performance and InnoDB fixes), and community contributors (timer, FreeBSD, toolchain). No duplication risk.

13.1 Functional Enablement

RocksDB (MyRocks) on riscv64 (MDEV-29875). The bundled RocksDB submodule must be updated to include upstream commits that fix riscv64 build failures. The primary required change is scoping the jemalloc_helper mm_malloc.h hack to glibc-on-Linux. The upstream RocksDB PRs (#14485, #14530) are the immediate unblocking action; once merged upstream, MariaDB needs to update its submodule reference (MDEV-16523, also open). Estimated effort: 1-2 person-weeks to audit the required upstream commits, validate the build on riscv64, and submit the submodule update PR. The Debian packaging team has implicitly solved this already; the MariaDB upstream has not.

MDEV-39142 release targeting. The InnoDB sv39 fix is merged but untargeted to a stable release as of research date. Advocacy to ensure the fix is included in the next stable maintenance releases (10.11.x, 11.4.x, 11.8.x) would ensure riscv64 deployments get a functional InnoDB without building from main. Estimated effort: 0.5 person-weeks of release coordination.

MDEV-24456 resolution. The main.join_outer test timeout on riscv64 has been open since December 2020 without investigation. Options are: (a) increase the test timeout for slow architectures, or (b) investigate whether the timeout reflects a genuine query planner regression on riscv64. Option (a) is a 1-hour fix if the timeout is purely a calibration issue. Option (b) requires hardware access and profiling. Estimated effort: 0.5-3 person-weeks depending on root cause.

13.2 Performance Optimization

CRC32c/CRC32 acceleration. Implementing crc32_riscv64.c using the RISC-V Zbc extension (carry-less multiply) would bring riscv64 CRC performance in line with amd64 and arm64. CRC32c is used for InnoDB page checksums (every page read and write), binlog checksums, and replication integrity. This is the highest-leverage single optimization available. Estimated effort: 3-5 person-weeks (implement, test on hardware with Zbc, integrate into cmake runtime dispatch). Requires RISC-V hardware with Zbc extension support.

Data not available: no published benchmark comparing crc32c_slow() vs hardware CRC on riscv64 MariaDB workloads. The relative impact depends on workload I/O intensity.

OpenSSL TLS acceleration. Contributing to or accelerating the open OpenSSL upstream PRs for riscv64 AES/ChaCha20/SHA would benefit MariaDB and every other TLS-using application on riscv64. This is out-of-scope for a MariaDB-specific investment but is complementary. See project-reports/openssl.md.

13.3 CI/CD Infrastructure

riscv64 CI in MariaDB’s GitLab pipeline. Adding a riscv64 build and test job to .gitlab-ci.yml is the highest-leverage infrastructure investment. Without it, every riscv64 regression requires external detection (Debian build failure, user report). MDEV-36217 showed a regression-to-fix cycle of approximately 1 month; CI would reduce this to days.

Implementation paths:

  • Native RISC-V hardware runner (requires runner registration with MariaDB Foundation or GitLab SaaS with riscv64 support)
  • QEMU emulation on an x86 GitLab runner (available today; slow but functional for build verification)
  • RISE-provided CI infrastructure if the RISE Platform WG offers runner capacity

The minimum viable CI is a build-only job running on QEMU, which would catch the class of regressions seen in MDEV-34815 and MDEV-36217. A full test run (mysql-test-run) on QEMU would likely take hours per run and is not practical for per-commit CI, but could be a weekly scheduled job.

Estimated effort: 2-4 person-weeks to author the CI configuration, validate on riscv64 (native or QEMU), and get it accepted by the MariaDB project.

13.4 Ecosystem Enablement

MariaDB’s dependent package ecosystem (plugins, connectors, ORMs) is addressed in the dependency section. The primary gap is the Python connector (mariadb on PyPI), which has no riscv64 wheel. Building and publishing a riscv64 wheel requires either cross-compilation with crossenv or a native RISC-V build environment. Estimated effort: 1-2 person-weeks including CI integration for wheel publishing. This is lower priority than the server-side functional and CI gaps.

13.5 Summary Table

Area Work Item Effort (person-weeks) Owner Priority
Functional Fix RocksDB (MyRocks) build on riscv64 (MDEV-29875): audit required upstream RocksDB commits, update bundled submodule 1-2 MariaDB contributor Critical
Functional Verify MDEV-39142 (InnoDB sv39 fix) is included in next stable maintenance releases 0.5 MariaDB contributor High
Functional Resolve MDEV-24456 join_outer test timeout: calibrate timeout for slow architectures 0.5-3 MariaDB contributor Low
Performance Implement CRC32c/CRC32 using RISC-V Zbc extension (crc32_riscv64.c) 3-5 MariaDB contributor (requires riscv64 Zbc hardware) High
CI/CD Add riscv64 build job to MariaDB GitLab CI (QEMU-based minimum, native hardware preferred) 2-4 MariaDB contributor / RISE Platform WG High
Ecosystem Build and publish riscv64 wheel for mariadb Python connector on PyPI 1-2 MariaDB contributor Low

14. Updates

No updates yet – initial report dated 2026-06-17.

15. References