Severe latency regression / TTFT spike on Gemini 3.8 Flash (High)

Google Antigravity
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1

Hi everyone,

I wanted to report a drastic degradation in service responsiveness and Time to First Token (TTFT) when using Gemini 3.8 Flash (High) in Antigravity today compared to yesterday.

I audited the conversation logs (transcript_full.jsonl) between two sessions on consecutive days:

  • Yesterday (Sep 14, ~13:00–14:15 UTC): Session 1721a93f-2f51-4713-b8e4-1f076c615bea
  • Today (Sep 15, ~12:17–12:25 UTC): Session 212a9c9a-d6aa-4492-964a-6a441eae1305

Here is the direct metric comparison:

Dimension Yesterday (1721a93f-2f51...) Today (212a9c9a-d6aa...)
Model Gemini 3.8 Flash (High) Gemini 3.8 Flash (High)
Time (UTC) 2026-09-14 13:05 – 14:15 (70 mins) 2026-09-15 12:17 – 12:25 (8.3 mins)
Total Steps / Turns 337 steps (8 user turns) 64 steps (1 user turn)
Tool Calls Made 153 calls (view_file, replace, grep) 31 calls (view_file, list_dir)
Median Step Turnaround 3.0 seconds 16.0 seconds
Min / Max Step Turnaround 1.0s / 21.0s 7.0s / 26.0s
Gross Step Throughput 83.1 tokens/sec 5.4 tokens/sec
Inferred TTFT Baseline ~0.8s – 1.8s ~14s – 25s

Key Observations from the Logs:

  1. TTFT on Minimal Prompts:
    To eliminate token generation time, I isolated steps with zero internal thinking (thinking = 0) that emitted single short tool calls (e.g., list_dir or view_file, ~20–25 tokens) with a minimal context window (< 1,000 tokens):
    • Yesterday: These calls consistently completed in 1.0 to 2.0 seconds.
    • Today: Identical small-context, zero-thinking calls consistently stalled for 15 to 26 seconds before returning.
  2. Impact on Agent Workflows:
    Because multi-step agent workflows rely on iterative tool loops, a 15–20s TTFT penalty per step grinds tasks to a near halt (dropping effective gross throughput from ~83 tok/s to ~5 tok/s).

Is anyone else observing severe backend queuing or high TTFT on the Flash endpoints today? Is there an ongoing service degradation or infrastructure incident being investigated?

2

Me too, from yesterday

3

still from yesterday the response i get from 3.8 flash very slower ? why google not address this issue publicly but people complaining acorss globally sameissue ,and still they dont yet solve ?? is there were sleeping from able to solve

4

Hi @gSys, @Arifloco @Peppe,

Thank you for reporting this. It was a known issue that has now been resolved.

Thanks everyone for your patience.

5

3.8 is slower than a turtle

6

This would be great! - We need a Antigravity status page!

7

According to u/SoundDr on Reddit, there was/should’ve been a limit reset. It never happened in my AGY CLI. Was the reset limited to regions/tiers/etc.?

8

@chunduriv Thanks for the update, but it looks like the issue is back - or was never fully fixed. I’m experiencing the exact same slowdown again right now (17:07 CEST today), same symptoms as before: extremely high TTFT, agent responses crawling even on trivial prompts. Could you confirm whether this is a regression or a separate incident? Would appreciate an updated status rather than marking it resolved prematurely.

9

Hi @Wojciech_Talar,

Is the issue still occurring? If so, please confirm if you are running the latest version of Antigravity. If it persists, kindly provide the trajectory IDs for further diagnosis.

10

Unfortunately, this problem has been occurring, especially since this morning. It’s not due to a lack of updates. I always have the latest version, but even a simple operation can still take up to 30 minutes…

11

I’m dealing with this too; also, the free-tier models are returning 503 errors.

Here’s another interesting observation regarding Antigravity: we’re seeing a huge number of related files that have nothing to do with the actual query—it’s pretty alarming.

12

It does seem like it’s back AGAIN after a few days