Skip to main content
New4.3 Million Vehicles, One Race Condition: What the Ford ITRM Recall Teaches Us About Cross-Layer DebuggingRead
Multi-File Comparison

Compare Logs Across Layers

Upload two or more log files and let Delta find the connections. Delta correlates events across layers, detects regressions, and reveals patterns that are invisible when looking at logs in isolation.

What Is Delta?

Delta is logcat.ai's multi-file comparison engine. Upload two or more log files — from different layers, different devices, or different time periods — and ask questions that span all of them.

Delta indexes every file, aligns timestamps, and cross-references events to find correlations that would take hours to discover manually. Whether you're debugging a cross-layer issue or hunting for a regression, Delta gives you answers that no single-file analysis can.

See It In Action

Watch Delta correlate events across multiple log files in real time

Delta Correlation Engine

Multi-file cross-layer analysis

Uploading...
Device Log (Firmware A)
10:15:01 kernel: usb 1-1: new device
10:15:02 systemd: Started app.service
10:15:03 kernel: BUG: sched while atomic
10:15:04 kernel: watchdog: timeout expired
Device Log (Firmware B)
10:15:01 kernel: usb 1-1: new device
10:15:02 systemd: Started app.service
10:15:03 app: request processed 42ms
10:15:04 kernel: all systems nominal
Kernel Log (OTA v3.2)
10:14:58 kernel: IRQ handler timeout
10:15:01 kernel: thermal zone0: 85°C
10:15:03 kernel: OOM killer invoked
10:15:04 kernel: process 1842 killed

Why Compare Logs?

The hardest bugs don't live in one log file

Multi-Source Issues

The kernel log says 'driver timeout,' the logcat shows 'service unavailable,' and the bugreport has a timing error — are they related? Without comparison, you'll never know.

Manual Correlation Is Slow

Aligning timestamps, mentally mapping events across files, and searching for cause-effect chains takes hours of expert time — if you even know what to look for.

Root Cause Spans Layers

The symptom appears in the app layer, but the root cause lives in the kernel or hardware driver layers. You can only see it when you look at all layers simultaneously.

Regressions Hide in Diffs

When comparing 'working' and 'broken' logs, the differences are subtle — a timing change, an extra error, a missing event. Automated comparison catches what humans miss.

Flexible by Design

Delta adapts to any comparison scenario — upload any combination of log files and let Delta figure out the connections

Cross-Layer Correlation

Modem
Logcat
Dmesg
Scanning timeline...

Upload multiple log files — logcat, dmesg, bugreport sections — and Delta finds related events across system layers. See how a low-level kernel event connects to a framework error and ultimately an app crash.

Regression Detection

v1.0 → v1.1
ActivityManager: START
WindowManager: focus
-GC: alloc 128MB
+GC: alloc 512MB
~OOM score: 250→900
+E/App: OutOfMemory

Compare logs from two software versions on the same device. Delta identifies what changed — new errors, timing shifts, missing events — so you know exactly what the update broke.

Device-to-Device

Device A
WiFi: connected
GPS: lock OK
BT: paired
Temp: 38C
Device B
WiFi: connected
GPS: no lock
BT: paired
Temp: 52C

Same software, different hardware. Upload logs from Device A and Device B to find device-specific behaviors, hardware quirks, or configuration differences.

Before/After Analysis

Before
Normal GC cycle
Alloc: 64MB
Stable heap
Change
After
Frequent GC
Alloc: 512MB
OOM crash

Compare logs from before and after a system update, configuration change, or firmware update to isolate the exact impact of the change.

Multi-Source Investigation

logcat.log
dmesg.log
traces.txt
events.log
↓ ↓ ↓ ↓
Processing...

Combine bugreport + kernel dmesg + logcat to build a complete picture. The more context you provide, the better the AI can trace cause-effect chains.

Field Test Comparison

📍Site A
-85 dBm
4G LTE
📍Site B
-112 dBm
No Service

Compare field test logs from different locations, times, or conditions. Identify environment-specific issues, time-of-day patterns, or configuration-specific behaviors.

Powerful Comparison Tools

AI-powered features designed for multi-file analysis

Timeline Alignment

Automatically synchronize timestamps across files, even when they use different formats or clock sources. See events in true chronological order.

Cross-Reference Detection

Delta identifies related events across files — matching error codes, correlated timestamps, cause-effect patterns — and highlights the connections.

Cross-File Deep Research

Ask questions that span all uploaded files. Deep Research searches across every log to build a comprehensive answer with evidence from multiple sources.

Shareable Results

Share your Delta analysis via link with team members. Everyone sees the same correlated view — no need to re-upload or re-analyze files.

How Delta Works

Four simple steps from upload to insight

1

Upload Your Files

Upload two or more log files — any combination of logcat, dmesg, bugreport, vendor tool exports, or other plaintext logs.

2

AI Indexes Everything

Delta processes all files, extracts events, aligns timestamps, and builds a unified searchable index across all your logs.

3

Ask Your Question

Ask anything — 'why did the app crash?', 'what changed between these versions?', 'is the kernel panic related to the framework error?'

4

Get Correlated Answers

Delta searches across all files, finds cross-references, and delivers a unified answer with evidence from every relevant source.

Who Uses Delta

Delta serves engineers across every vertical and every stage of the development lifecycle

Device & Platform Engineers

Compare bugreports across BSP versions, correlate kernel logs with framework crashes on phones, tablets, and IoT devices.

Telecom Engineers

Diff modem diagnostic traces before and after firmware updates, correlate NAS/RRC events with RIL logs to isolate call drops and registration failures.

Automotive Engineers

Compare CAN bus traces across ECU firmware versions, correlate VHAL events with IVI bugreports to trace vehicle software regressions.

QA & Release Teams

Compare logs from passing vs. failing test runs across any device type or vertical. Detect regressions by identifying exactly what changed between software versions.

Frequently Asked Questions

Common questions about Delta comparison

Delta supports comparing two or more files simultaneously. The more context you provide, the better the AI can correlate events and identify patterns across sources.

Delta supports any plaintext log format — logcat, dmesg, bugreport, vendor tool exports, and any other human-readable log files. You can mix and match different formats in a single comparison.

No. You can compare logs from different devices, different software versions, or even different platforms. Delta is flexible — use it for device-to-device comparison, regression detection, or any multi-source investigation.

Yes. Delta handles logs from different time periods. This is useful for before/after comparisons, regression detection across builds, and comparing field test logs from different sessions.

Upload logs from a 'working' version and a 'broken' version. Delta identifies differences — new errors that appeared, events that stopped occurring, timing changes, and behavioral shifts — helping you pinpoint exactly what the update broke.

Yes. Delta automatically detects and normalizes timestamp formats across files, aligning events chronologically even when files use different date/time formats or clock sources.

Yes. All files are processed in isolated environments, encrypted at rest and in transit, and never shared between users. Your comparison data is private to your account.

Start Comparing Your Logs

Upload two or more log files and discover the connections hiding between them