From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f172.google.com (mail-pf1-f172.google.com [209.85.210.172]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 75BF6146A66 for ; Tue, 31 Mar 2026 07:02:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774940558; cv=none; b=IhHidS6nnMMA6wccu0SJueG055xDNlqQKod0ztzpUdTLg48eoCrYCNwSInSoq3SO46pvkslkyEitIIqVwbgyI+5ey4Dodr0ybP4telAeQfuZEozrHXahU0cDv3QPpB13ZwxtBoqOuD6KQRFbvZ+RqJSGF5RmJ1oio/sjhdc4VwU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774940558; c=relaxed/simple; bh=vfsfPTAFa+cjfR+3AJsOAX51DLByk6M5kVtNWODXYtM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=r70zU/XegCCvV730lzx16KFAn8SjKcG+yE/DWAth1KP/PBYM9JVPygqgCIAlLuO9Pun20e2x2Iu4cj/PbirCbB+CU4bEPAlkuKinlvJiF4TtAMe8RqlAO5G6fV2JZ8hM6wGsVHt+OTalUgF3DeSzNnmC+LTKRJjzW9y5pI9ZCMo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org; spf=pass smtp.mailfrom=chromium.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b=YBEah2FB; arc=none smtp.client-ip=209.85.210.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=chromium.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=chromium.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="YBEah2FB" Received: by mail-pf1-f172.google.com with SMTP id d2e1a72fcca58-82c4b5dfe6cso2413032b3a.2 for ; Tue, 31 Mar 2026 00:02:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1774940557; x=1775545357; darn=vger.kernel.org; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=O3Es0Jq2Oqy/D3XNICPyfENzALak9AF3Vg+PltBwZmY=; b=YBEah2FB20zapO4U1MFK4dt/8JCwTu5aF1PN9EsHOmVxq7tQtrJoB2vNMKxeuXSoxh W4woFlh7xqF5K4lDpH5DWbPZCQAEqztYRFPxcE5MHNo4wI7XqMFNRlx0Wbz1KGVTBx3j 2YWzkor+kOeUinr8uT0EKFMfI3JfmIzauKJg4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1774940557; x=1775545357; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-gg:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=O3Es0Jq2Oqy/D3XNICPyfENzALak9AF3Vg+PltBwZmY=; b=Ql0b6Ip39A/HJZjlJ/j8eQQmnQLbHG6Szqg5CAyi14/dVmrG223tvCMtRmHD1IAlqB XmDnmfQD7n5omJCrSM263BqqNBB5k/057F4pZEJ1uDdMnWTYoo110lzH5KOdV2iBeKzv TQQPOLmOYjKgv0BRgJWhNFzi0CWgrvcMp5d/AmqAcZDD8/eNVGFTkhWBzYRtYxYvY5/G hMW/tpUxhefsbVhFQEqxBRa/9sF1gc/r97OQFD9mh6mStzso5B3cNbJdLT/cZBotN4Dh hjcsAseBgjdUHLo08GMLjeNq2VwIKtMIi29ozGfxneOOR4XRGwjhS/7Gx2mTJioworbz yqWg== X-Gm-Message-State: AOJu0YzYj0JlCA9M6SyZlG5M9U5aVLlfhUHlrIQkgQKLgKfEOr859D9x XuOwVYhmAd/9gYHJpuFsdof61K5T+OtN19wEf+y2l08P+UnEJZVaawJP1MKWbTFY6A== X-Gm-Gg: ATEYQzziXB9j/5Vk0siORmEraXAvXkMYBFmVW+Zf81WaM2VhRm9yKGcnS8UiHaoKSTa 0+GdBKQZQ30iGJ05vsOrLT5KhkqvPm1u+9XGExqQBN3DZ4sZOOMKI2COQJu5OvkxI84AAYK6E7d H1v2W1v1HMXgxuvJEuN8gRXf8SdD5aSUmPjAQM7BVD3mw1BJzYwoS4z9fovI4gx2vJHTVpGauj0 nZUEttpuH6vdqRPIcS/JmILzbbBEOF/n8gA6xX2dTqFuNbXSi9LHIFbVb1g6F5ynbIRZuvrHJgO PLCXSRvrS+WsNucB/DtDa5ZEZ2BR4LEAcTHJKZhTo7VGVYIifEaA8whMhqS1qaItZRO03UMa/up qho/QOjdjt5hvSCbmXWL/CTHr+2WFFly6FpohJaLXK+3C+YF15UIOYB3b/nqr1tbZjztswv/V+M rjFoLSWCFu2SAssdfLW8T4QNYc/36ZZnz2arzhrJXDGtHfX3x5vNSABXChR8XH9lE= X-Received: by 2002:a05:6a00:b486:b0:82a:7734:8c6a with SMTP id d2e1a72fcca58-82c960a484emr14265866b3a.48.1774940556821; Tue, 31 Mar 2026 00:02:36 -0700 (PDT) Received: from google.com ([2a00:79e0:2031:6:90ef:61f3:1679:56f5]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-82cdd04bb0esm865819b3a.38.2026.03.31.00.02.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 31 Mar 2026 00:02:36 -0700 (PDT) Date: Tue, 31 Mar 2026 16:02:32 +0900 From: Sergey Senozhatsky To: Qu Wenruo Cc: "linux-block@vger.kernel.org" , minchan@kernel.org, senozhatsky@chromium.org Subject: Re: Super slow subpage IO on zram block devices? Message-ID: References: <92361cd3-fb8b-482e-bc89-15ff1acb9a59@suse.com> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <92361cd3-fb8b-482e-bc89-15ff1acb9a59@suse.com> On (26/03/31 16:15), Qu Wenruo wrote: > # time blkdiscard -p 4k /dev/zram0 > [ It takes too long time that exceed my patient ] It's not you, I bet no one has this much patience, because that's basically a "deadlock". I'll send a patch quickly. Thanks for the report.