PulseAugur
EN
LIVE 07:21:18

Qwen 3.8 27B LLM praised for capabilities but criticized for overthinking default

By PulseAugur Editorial · [14 sources] ·

Alibaba's Qwen research lab has released Qwen 3.8 27B, an open-source, vision-capable LLM. While praised for its capabilities and size, suitable for local hardware, users are reporting that its default setting for reasoning effort leads to excessive "overthinking." This can result in significantly longer processing times for even simple tasks, with some users struggling to complete tasks that previous versions or other models handle much faster. Adjusting the reasoning effort setting to lower levels can mitigate this issue, though some users are still experimenting to find optimal configurations. AI

IMPACT The default "overthinking" behavior of Qwen 3.8 27B highlights the challenges in balancing model capability with efficient resource utilization for local deployments.

RANK_REASON The cluster consists of blog posts and social media discussions about a recently released model, focusing on user experiences and performance quirks rather than an official release announcement from the lab itself.

Read on r/LocalLLaMA →

AI-generated summary · Google Gemini · from 14 sources. How we write summaries →

Qwen 3.8 27B LLM praised for capabilities but criticized for overthinking default

COVERAGE [14]

  1. Simon Willison TIER_1 English(EN) ·

    Qwen 3.8 27B is excellent, but it defaults to wildly overthinking things

    <p>Friday's big release was <a href="https://huggingface.co/Qwen/Qwen3.8-27B">Qwen 3.8 27B</a>, an Apache 2 licensed 27B parameter vision-capable LLM from Alibaba's Qwen research lab. I've been looking forward to this one: 27B is an excellent size for running a model on a reasona…

  2. r/LocalLLaMA TIER_1 English(EN) · /u/Altruistic_Heat_9531 ·

    Qwen 3.8 27B Overthinking, It has to be done, it has to be overthinking to punch Opus 4.6

    <!-- SC_OFF --><div class="md"><p>Yes, it sucks to waste time waiting on 16K+ reasoning tokens alone. But here's the thing, this is only a 27B model trying to perform on par with 1T+ parameter models. Something has to be sacrificed, and that sacrifice is the amount of reasoning o…

  3. Mastodon — fosstodon.org TIER_1 English(EN) · [email protected] ·

    Qwen 3.8 27B is excellent, but it defaults to wildly overthinking things https:// lobste.rs/s/k7myyp # ai # vibecoding https:// simonwillison.net/2026/Aug/16/ q

    Qwen 3.8 27B is excellent, but it defaults to wildly overthinking things https:// lobste.rs/s/k7myyp # ai # vibecoding https:// simonwillison.net/2026/Aug/16/ qwen-38-27b/

    LINKS lobste.rs/…/k7myyp simonwillison.net/…/qwen-38-27b simonwillison.net/…/16
  4. Mastodon — fosstodon.org TIER_1 English(EN) · [email protected] ·

    Qwen 3.8 27B is excellent, but it defaults to wildly overthinking things https://simonwillison.net/2026/Aug/16/qwen-38-27b/ # AI # LLM # Tech

    Qwen 3.8 27B is excellent, but it defaults to wildly overthinking things https://simonwillison.net/2026/Aug/16/qwen-38-27b/ # AI # LLM # Tech

    LINKS simonwillison.net/…/qwen-38-27b
  5. r/LocalLLaMA TIER_1 English(EN) · /u/sukazu ·

    Unpopular opinion : Qwen 3.8 27b is not an overthinker

    <!-- SC_OFF --><div class="md"><p>Yes it uses a ton more reasoning tokens than 3.6 did</p> <p>But test in on the same tasks with the other chinese models, glm 5.3, deepseek v4 flash and pro, etc it's really similar, and they are needed</p> <p>The reality is, we're just frustrated…

  6. r/LocalLLaMA TIER_1 English(EN) · /u/MikeNonect ·

    How to stop Qwen3.8-27b from overthinking

    <!-- SC_OFF --><div class="md"><p>I see a lot of people struggle with Qwen3.8-27b overthinking, and I wanted to share a really straightforward fix that works for me.</p> <p>Before setting these llamacpp flags, I often had Qwen thinking for over 90 minutes, which was really imprac…

  7. r/LocalLLaMA TIER_1 English(EN) · /u/maxwell321 ·

    Long Review: Qwen 3.8 27B is VERY good at tapping into it's real-world knowledge. It's "overthinking" brings it to Sonnet level performance with the potential for Opus level results.

    <table> <tr><td> <a href="https://www.reddit.com/r/LocalLLaMA/comments/1vqm51f/long_review_qwen_38_27b_is_very_good_at_tapping/"> <img alt="Long Review: Qwen 3.8 27B is VERY good at tapping into it's real-world knowledge. It's &quot;overthinking&quot; brings it to Sonnet level pe…

  8. Mastodon — fosstodon.org TIER_1 English(EN) · [email protected] ·

    Qwen 3.8 27B is excellent, but it defaults to overthinking things https:// simonwillison.net/2026/Aug/16/ qwen-38-27b/ Comments: https:// news.ycombinator.com/i

    Qwen 3.8 27B is excellent, but it defaults to overthinking things https:// simonwillison.net/2026/Aug/16/ qwen-38-27b/ Comments: https:// news.ycombinator.com/item?id=4 9324985 # HackerNews # Qwen3 .8 # Overthinking # AI # TechNews # Innovation

    LINKS simonwillison.net/…/qwen-38-27b simonwillison.net/…/16
  9. r/LocalLLaMA TIER_1 English(EN) · /u/NelsonMinar ·

    Simon Willison: Qwen 3.8 27B is excellent, but it defaults to wildly overthinking things

    <!-- SC_OFF --><div class="md"><p>I look to Simon for a broad survey of current LLM tech. Here's <a href="https://simonwillison.net/2026/Aug/16/qwen-38-27b/">his review of playing with Qwen 3.8 27B</a>. His comment <a href="https://fedi.simonwillison.net/@simon/117107511994840560…

  10. r/LocalLLaMA TIER_1 (TL) · /u/LippyBumblebutt ·

    Qwen 3.8-27b unusable long thinking?

    <!-- SC_OFF --><div class="md"><p>I have a small coding test, where I ask a model to implement a simple CLI from a spec file. Qwen3.6-27b can do it in ~50k tokens.</p> <p>Qwen3.<em>8</em>-27b uses an absurd amount of thinking. I did a few runs, but never finished a single one, be…

  11. r/LocalLLaMA TIER_1 English(EN) · /u/germangrower69 ·

    Anyone managed to get Qwen 3.8 27B running smoothly on vLLM? Can't get rid of endless thinking

    <!-- SC_OFF --><div class="md"><p>Title pretty much says it all. I’ve deployed Qwen 3.8 27B using vLLM on an RTX 6000 Pro (tried multiple vLLM releases and launch recipes), but I can't get it into a usable state because of crazy long reasoning passes.</p> <p>Regardless of the thi…

  12. Mastodon — mastodon.social TIER_1 English(EN) · [email protected] ·

    Qwen 3.8 27B is excellent, but it defaults to overthinking things Article URL: https:// simonwillison.net/2026/Aug/16/ qwen-38-27b/ Comments URL: https:// news.

    Qwen 3.8 27B is excellent, but it defaults to overthinking things Article URL: https:// simonwillison.net/2026/Aug/16/ qwen-38-27b/ Comments URL: https:// news.ycombinator.com/item?id=4 9324985 Points: 17 # Comments: 3 https:// simonwillison.net/2026/Aug/16/ qwen-38-27b/ # Tech #…

    LINKS simonwillison.net/…/qwen-38-27b simonwillison.net/…/16
  13. Mastodon — mastodon.social TIER_1 English(EN) · [email protected] ·

    Qwen 3.8 27B is excellent, but it defaults to overthinking things https://simonwillison.net/2026/Aug/16/qwen-38-27b/ # HackerNews # Tech # AI

    Qwen 3.8 27B is excellent, but it defaults to overthinking things https://simonwillison.net/2026/Aug/16/qwen-38-27b/ # HackerNews # Tech # AI

    LINKS simonwillison.net/…/qwen-38-27b
  14. Mastodon — mastodon.social TIER_1 English(EN) · [email protected] ·

    Qwen 3.8 27B is excellent, but it defaults to wildly overthinking things https://simonwillison.net/2026/Aug/16/qwen-38-27b/ # AI # LLM # OpenSource

    Qwen 3.8 27B is excellent, but it defaults to wildly overthinking things https://simonwillison.net/2026/Aug/16/qwen-38-27b/ # AI # LLM # OpenSource

    LINKS simonwillison.net/…/qwen-38-27b

RELATED ENTITIES

RELATED TOPICS