Repository Analysis

scylladb/seastar

High performance server-side application framework

9.5 Low AI signal View on GitHub

Analysis Overview

This report presents the forensic synthetic code analysis of scylladb/seastar, a C++ project with 9,305 GitHub stars. SynthScan v2.0 examined 20,158 lines of code across 104 source files, recording 145 pattern matches distributed across 10 syntactic categories. The overall adjusted score of 9.5 places this repository in the Low AI signal band.

The scanner applied 160+ deterministic lexical heuristics, multi-line block detectors, abstract syntax tree depth profilers, and a cross-file Jaccard similarity matrix to construct a statistically normalised synthetic code estimate. All matches are individually weighted by severity coefficient and contextual multiplier before summation, and the resulting headline score is temporally discounted to account for the repository's development history relative to the commercial emergence of large language model coding tooling (November 2022 onward).

9.5
Adjusted Score
9.5
Raw Score
100%
Time Factor
2026-07-14
Last Push
9.3K
Stars
C++
Language
20.2K
Lines of Code
104
Files
145
Pattern Hits
2026-07-14
Scan Date
0.01
HC Hit Rate

What These Metrics Mean

Adjusted Score
Primary synthetic code indicator. Raw score normalised per 1,000 lines of code and multiplied by the temporal discount factor. This is the definitive comparative metric — use it to rank repositories by AI authorship density.
Raw Score
The unmodified sum of all severity-weighted, context-multiplied pattern match scores before temporal discounting. Reflects the absolute signal strength independent of when the repository was last active.
Time Factor
The temporal discount multiplier (0–100%) applied to the raw score. Repositories last updated before ChatGPT's launch (Nov 2022) receive a 5% factor. Full signal is only assigned to repositories active in the post-adoption era (Jan 2024+).
Pattern Hits
Total count of individual pattern matches across all files and categories. A high hit count with a low score may indicate a very large codebase with isolated AI snippets; a low count with a high score indicates dense, concentrated AI signatures.
HC Hit Rate
High+Critical pattern hits per file, averaged across the repository. This orthogonal signal catches repositories where a few files are densely packed with high-severity AI tells — a strong indicator even when the normalised score appears moderate due to codebase size.
Lines of Code / Files
Total lines and files analysed. The scanner examines 94 file extensions. These denominators are used to normalise the score, enabling fair comparison between repositories of vastly different sizes.

Score History

Longitudinal tracking requires multiple scan runs. Once this repository is re-scanned after new commits land, this chart will visualise how the synthetic code signal evolves over time — enabling you to detect whether AI authorship is growing, stabilising, or being actively corrected by human engineers.

No multi-scan history yet — run the scanner again to build trend data.

Severity Breakdown

Classifies detected patterns by their diagnostic confidence and structural impact. CRITICAL patterns (coefficient 10) represent definitive synthetic signatures — hallucinated imports, explicit LLM attribution metadata — virtually never produced by human authors. HIGH (5) indicates strong structural tells such as cross-file repetition or cross-linguistic idioms. MEDIUM (2) covers recognisable conversational padding and AI-specific vocabulary. LOW (1) captures subtle indicators like tautological comments and generic boilerplate that require density to carry independent signal.

CRITICAL 0HIGH 1MEDIUM 20LOW 124

Directory Score Breakdown

This horizontal bar chart decomposes the repository's raw synthetic code score by top-level directory, allowing you to pinpoint precisely which modules or components carry the highest AI authorship density. Directories with disproportionately high scores relative to their size warrant targeted manual review: concentrated AI signatures often trace back to mass-generated configuration layers, auto-ported test suites, LLM-scaffolded boilerplate classes, or entire subsystems authored under heavy copilot assistance. Use this view to prioritise your human code-review effort.

Pattern Findings

The scanner identified 145 distinct pattern matches across 10 syntactic categories. Each entry below represents a discrete location in the source code where the engine recorded a statistically significant AI authorship indicator. Expand any category row to inspect the individual file paths, line numbers, code snippets, and the lexical context (CODE, COMMENT, or STRING) in which each match was detected.

Reading the findings table: The Severity column indicates the diagnostic confidence level (CRITICAL / HIGH / MEDIUM / LOW). The Context column identifies whether the match occurred inside executable code, an inline comment, or a string literal — comment-context matches receive a ×1.5 weight because LLMs systematically over-annotate. The ⚡ bolt icon marks clustered matches: three or more patterns within a 10-line window, each receiving an additional ×1.5 density multiplier as dense clusters constitute far stronger evidence of synthetic authorship than isolated hits.

Over-Commented Block54 hits · 54 pts
SeverityFileLineSnippetContext
LOWCMakeLists.txt1#COMMENT
LOWCMakeLists.txt361# We set the following environment variablesCOMMENT
LOWCMakeLists.txt1061# Without these rules, a broader -ffile-prefix-map=<project_root>=. (typicallyCOMMENT
LOWCMakeLists.txt1401#COMMENT
LOWconfigure.py1#!/usr/bin/env python3COMMENT
LOWseastar_cmake.py1# This file is open source software, licensed to you under the termsCOMMENT
LOWtest.py1#!/usr/bin/env python3COMMENT
LOWcooking.sh1#!/bin/bashCOMMENT
LOWcooking.sh241fiCOMMENT
LOWinstall-dependencies.sh1#!/bin/bashCOMMENT
LOWcmake/check-seastar-include-style.py1#!/usr/bin/env python3COMMENT
LOWtests/CMakeLists.txt1#COMMENT
LOWtests/unit/CMakeLists.txt1#COMMENT
LOWtests/unit/CMakeLists.txt61# [KIND {SEASTAR,BOOST,CUSTOM,FUZZ}]COMMENT
LOWtests/unit/CMakeLists.txt241 set_tests_properties (${test_name_prefix}.${name}COMMENT
LOWtests/unit/io_trace_test.py1#!/usr/bin/env python3COMMENT
LOWtests/unit/json2code_test.py1#!/usr/bin/env python3COMMENT
LOWtests/unit/prometheus_test.py1#!/usr/bin/env python3COMMENT
LOWtests/unit/prometheus_test.py101 if not isinstance(other, Exposition):COMMENT
LOWtests/unit/https-server.py1#!/usr/bin/env python3COMMENT
LOW…/manual/iosched_reproducers/scylla_tablet_migration.sh1#!/usr/bin/env bashCOMMENT
LOWtests/fuzz/CMakeLists.txt1#COMMENT
LOWtests/perf/CMakeLists.txt1#COMMENT
LOWscripts/tap.sh1#COMMENT
LOWscripts/posix_net_conf.sh1#!/bin/bashCOMMENT
LOWscripts/run_with_dpdk.sh1#!/bin/bashCOMMENT
LOWscripts/addr2line.py1#!/usr/bin/env python3COMMENT
LOWscripts/seastar-json2code.py1#!/usr/bin/env python3COMMENT
LOWscripts/stall-analyser.py301 self.collapsed = defaultdict(int)COMMENT
LOWscripts/stall-analyser.py421 for s in args.file:COMMENT
LOWscripts/dpdk_nic_bind.py1#!/usr/bin/env python2COMMENT
LOWscripts/dpdk_nic_bind.py21#COMMENT
LOWscripts/perftune.py721 """COMMENT
LOWscripts/perftune.py901 # application thread that sent a packet on the same TCP stream.COMMENT
LOWscripts/perftune.py981 top_slaves_list = set(itertools.chain.from_iterable(COMMENT
LOWscripts/perftune.py1281 # in order to serve XSK by the higher RPS queues and RSS by the lower ones.COMMENT
LOWscripts/perftune.py1521 perftune_print("Setting non-NVMe disks: {}...".format(", ".join(non_nvme_disks)))COMMENT
LOWscripts/perftune.yaml1# Mode is one of the following values:COMMENT
LOWscripts/perftune.yaml21COMMENT
LOW.github/workflows/gen-matrix.py1#!/usr/bin/env -S uv run --scriptCOMMENT
LOW.github/workflows/install-build-env.sh1#!/usr/bin/env bashCOMMENT
LOW.github/workflows/install-build-env.sh21# Install the seastar build toolchain and run ./configure.py inside theCOMMENT
LOWdoc/htmlsplit.py1#!/usr/bin/env python3COMMENT
LOWapps/CMakeLists.txt1# This file is open source software, licensed to you under the termsCOMMENT
LOWapps/io_tester/CMakeLists.txt1#COMMENT
LOWapps/rpc_tester/CMakeLists.txt1#COMMENT
LOWapps/memcached/CMakeLists.txt1#COMMENT
LOWapps/memcached/tests/CMakeLists.txt1#COMMENT
LOWapps/memcached/tests/test.py1#!/usr/bin/env python3COMMENT
LOWapps/memcached/tests/test_memcached.py1#!/usr/bin/env python3COMMENT
LOWapps/httpd/CMakeLists.txt1#COMMENT
LOWapps/iotune/CMakeLists.txt1#COMMENT
LOWapps/seawreck/CMakeLists.txt1#COMMENT
LOWdemos/CMakeLists.txt1#COMMENT
Self-Referential Comments16 hits · 48 pts
SeverityFileLineSnippetContext
MEDIUMconfigure.py3# This file is open source software, licensed to you under the termsCOMMENT
MEDIUMseastar_cmake.py1# This file is open source software, licensed to you under the termsCOMMENT
MEDIUMtest.py3# This file is open source software, licensed to you under the termsCOMMENT
MEDIUMinstall-dependencies.sh3# This file is open source software, licensed to you under the termsCOMMENT
MEDIUMcmake/check-seastar-include-style.py3# This file is open source software, licensed to you under the termsCOMMENT
MEDIUMtests/unit/io_trace_test.py3# This file is open source software, licensed to you under the termsCOMMENT
MEDIUMtests/unit/json2code_test.py3# This file is open source software, licensed to you under the termsCOMMENT
MEDIUMtests/unit/prometheus_test.py3# This file is open source software, licensed to you under the termsCOMMENT
MEDIUMtests/unit/https-server.py3# This file is open source software, licensed to you under the termsCOMMENT
MEDIUMscripts/tap.sh2# This file is open source software, licensed to you under the termsCOMMENT
MEDIUMscripts/addr2line.py3# This file is open source software, licensed to you under the termsCOMMENT
MEDIUM.github/workflows/gen-matrix.py3# This file is open source software, licensed to you under the termsCOMMENT
MEDIUM.github/workflows/install-build-env.sh3# This file is open source software, licensed to you under the termsCOMMENT
MEDIUMdoc/htmlsplit.py13# This file is open source software, licensed to you under the termsCOMMENT
MEDIUMapps/memcached/tests/test.py3# This file is open source software, licensed to you under the termsCOMMENT
MEDIUMapps/memcached/tests/test_memcached.py3# This file is open source software, licensed to you under the termsCOMMENT
Hyper-Verbose Identifiers41 hits · 46 pts
SeverityFileLineSnippetContext
LOWconfigure.py128def resolve_compilers_for_compiler_cache(args, compiler_cache):CODE
LOWseastar_cmake.py37def convert_strings_to_cmake_list(*args):CODE
LOWtests/unit/prometheus_test.py265 def test_filtering_by_label_sans_aggregation(self) -> None:CODE
LOWtests/unit/prometheus_test.py285 def test_filtering_by_label_with_aggregation(self) -> None:CODE
LOWtests/manual/rl-iosched.py204def mixed_run_and_show_results(m, ioprop):CODE
LOWtests/manual/rl-iosched.py266def limits_run_and_show_results(m):CODE
LOWtests/manual/rl-iosched.py302def isolation_show_stat_header():CODE
LOWtests/manual/rl-iosched.py307def isolation_run_and_show_results(m):CODE
LOWtests/manual/rl-iosched.py333def class_limit_show_stat_header():CODE
LOWtests/manual/rl-iosched.py338def class_limit_run_and_show_results(m):CODE
LOWscripts/addr2line.py436 def _backtrace_context_matches(self):CODE
LOWscripts/stall-analyser.py388def print_command_line_options(args):STRING
LOWscripts/perftune.py1454 def enforce_preferred_clocksource(self):CODE
LOWscripts/perftune.py1463 def preferred_clocksource_available(self):CODE
LOWscripts/perftune.py1466 def recommendation_if_unavailable(self):CODE
LOWscripts/perftune.py216def learn_irqs_from_proc_interrupts(pattern, irq2procline):CODE
LOWscripts/perftune.py338def check_sysfs_numa_topology_is_valid():CODE
LOWscripts/perftune.py426 def compute_cpu_mask_for_mode(mq_mode, cpu_mask):CODE
LOWscripts/perftune.py1099 def __virtio_irq_to_queue_idx(self, irq):CODE
LOWscripts/perftune.py1181 def __get_irq_to_queue_idx_functor(self, iface):CODE
LOWscripts/perftune.py1212 def __irq_lower_bound_by_queue(self, iface, irqs, queue_idx):CODE
LOWscripts/perftune.py1334 def __setup_one_tunable_iface(self, iface):CODE
LOWscripts/perftune.py1582 def __nvme_fast_path_irq_filter(self, irq):CODE
LOWscripts/perftune.py1606 def __group_disks_info_by_type(self):CODE
LOWapps/memcached/tests/test_memcached.py147 def test_recovers_from_errors_in_the_stream(self):CODE
LOWapps/memcached/tests/test_memcached.py152 def test_incomplete_command_results_in_error(self):CODE
LOWapps/memcached/tests/test_memcached.py160 def test_stream_closed_results_in_error(self):CODE
LOWapps/memcached/tests/test_memcached.py167 def test_unsuccesful_parsing_does_not_leave_data_behind(self):CODE
LOWapps/memcached/tests/test_memcached.py211 def test_connection_statistics(self):CODE
LOWapps/memcached/tests/test_memcached.py228 def test_large_response_is_split_into_mtu_chunks(self):CODE
LOWapps/memcached/tests/test_memcached.py264 def test_expiry_at_epoch_time(self):CODE
LOWapps/memcached/tests/test_memcached.py271 def test_multiple_keys_in_get(self):CODE
LOWapps/memcached/tests/test_memcached.py284 def test_keys_set_after_flush_remain(self):CODE
LOWapps/memcached/tests/test_memcached.py291 def test_flush_all_with_timeout_flushes_all_keys_even_those_set_after_flush(self):CODE
LOWapps/memcached/tests/test_memcached.py301 def test_subsequent_flush_is_merged(self):CODE
LOWapps/memcached/tests/test_memcached.py313 def test_immediate_flush_cancels_delayed_flush(self):CODE
LOWapps/memcached/tests/test_memcached.py322 def test_flushing_in_the_past(self):CODE
LOWapps/memcached/tests/test_memcached.py333 def test_memcache_does_not_crash_when_flushing_with_already_expred_items(self):CODE
LOWapps/memcached/tests/test_memcached.py338 def test_response_spanning_many_datagrams(self):CODE
LOWapps/memcached/tests/test_memcached.py396 def test_how_stats_change_with_different_commands(self):CODE
LOWapps/memcached/tests/test_memcached.py543 def test_incr_and_decr_on_invalid_input(self):CODE
Deep Nesting17 hits · 16 pts
SeverityFileLineSnippetContext
LOWtests/unit/io_trace_test.py111CODE
LOWtests/unit/prometheus_test.py138CODE
LOWscripts/addr2line.py149CODE
LOWscripts/addr2line.py490CODE
LOWscripts/seastar-json2code.py214CODE
LOWscripts/seastar-json2code.py381CODE
LOWscripts/seastar-json2code.py403CODE
LOWscripts/seastar-json2code.py536CODE
LOWscripts/stall-analyser.py348CODE
LOWscripts/stall-analyser.py388CODE
LOWscripts/stall-analyser.py206CODE
LOWscripts/stall-analyser.py225CODE
LOWscripts/perftune.py121CODE
LOWscripts/perftune.py261CODE
LOWscripts/perftune.py426CODE
LOWscripts/perftune.py779CODE
LOWscripts/perftune.py1695CODE
AI Slop Vocabulary3 hits · 9 pts
SeverityFileLineSnippetContext
MEDIUM…/manual/iosched_reproducers/scylla_tablet_migration.sh12# The batch workload does large sequential reads and wants to utilize allCOMMENT
MEDIUM…oducers/one_cpu_starved_shard_can_still_saturate_io.sh5# Goal: it should be able to utilize the entire bandwidth of the disk,COMMENT
MEDIUMscripts/addr2line.py100 # will just exit. We need to be robust against that. WeCOMMENT
Cross-Language Confusion1 hit · 8 pts
SeverityFileLineSnippetContext
HIGHconfigure.py55 # We can't write to /dev/null, since in some cases (-ftest-coverage) gcc will create an auxiliaryCOMMENT
Unused Imports4 hits · 4 pts
SeverityFileLineSnippetContext
LOWtests/manual/rl-iosched.py4CODE
LOWtests/manual/rl-iosched.py10CODE
LOWapps/memcached/tests/test.py19CODE
LOWapps/memcached/tests/test.py20CODE
Excessive Try-Catch Wrapping6 hits · 4 pts
SeverityFileLineSnippetContext
LOWscripts/seastar-json2code.py391 except Exception as e:STRING
LOWscripts/seastar-json2code.py666 except Exception as e:STRING
LOWscripts/seastar-json2code.py681 except Exception as e:STRING
LOWscripts/seastar-json2code.py706 except Exception as e:STRING
MEDIUMscripts/seastar-json2code.py707 print("Error while parsing JSON file '" + param + "' error " + str(e))STRING
LOWscripts/perftune.py2121except Exception as e:CODE
AI Structural Patterns2 hits · 2 pts
SeverityFileLineSnippetContext
LOWscripts/addr2line.py348CODE
LOWscripts/stall-analyser.py225CODE
Redundant / Tautological Comments1 hit · 2 pts
SeverityFileLineSnippetContext
LOWtests/unit/io_trace_test.py86 # Check if lttng-sessiond is running (or can be started)COMMENT