From: Barry Song <21cnbao@gmail.com>
To: kasong@tencent.com
Cc: linux-mm@kvack.org, Andrew Morton <akpm@linux-foundation.org>,
David Hildenbrand <david@kernel.org>,
Lorenzo Stoakes <lorenzo.stoakes@oracle.com>,
Zi Yan <ziy@nvidia.com>,
Baolin Wang <baolin.wang@linux.alibaba.com>,
Hugh Dickins <hughd@google.com>, Chris Li <chrisl@kernel.org>,
Kemeng Shi <shikemeng@huaweicloud.com>,
Nhat Pham <nphamcs@gmail.com>, Baoquan He <bhe@redhat.com>,
Johannes Weiner <hannes@cmpxchg.org>,
Yosry Ahmed <yosry.ahmed@linux.dev>,
Youngjun Park <youngjun.park@lge.com>,
Chengming Zhou <chengming.zhou@linux.dev>,
Roman Gushchin <roman.gushchin@linux.dev>,
Shakeel Butt <shakeel.butt@linux.dev>,
Muchun Song <muchun.song@linux.dev>,
Qi Zheng <zhengqi.arch@bytedance.com>,
linux-kernel@vger.kernel.org, cgroups@vger.kernel.org
Subject: Re: [PATCH RFC 12/15] mm, swap: merge zeromap into swap table
Date: Wed, 25 Feb 2026 20:19:14 +0800 [thread overview]
Message-ID: <CAGsJ_4yv31utMTsZcRf5adeUzC7NnE0DfMKRFi3v1iCxfdXbdw@mail.gmail.com> (raw)
In-Reply-To: <20260220-swap-table-p4-v1-12-104795d19815@tencent.com>
On Fri, Feb 20, 2026 at 7:42 AM Kairui Song via B4 Relay
<devnull+kasong.tencent.com@kernel.org> wrote:
>
> From: Kairui Song <kasong@tencent.com>
>
> By reserving one bit for the counting part, we can easily merge the
> zeromap into the swap table.
Hi Kairui,
I know you're saving space by removing the zeromap memory,
but do you think a bitmap can sometimes be faster
than iterating over multiple data points to set or get bits?
Or is the performance difference too small to notice?
Thanks
Barry
next prev parent reply other threads:[~2026-02-25 12:19 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-02-19 23:42 [PATCH RFC 00/15] mm, swap: swap table phase IV with dynamic ghost swapfile Kairui Song via B4 Relay
2026-02-19 23:42 ` [PATCH RFC 01/15] mm: move thp_limit_gfp_mask to header Kairui Song via B4 Relay
2026-02-19 23:42 ` [PATCH RFC 02/15] mm, swap: simplify swap_cache_alloc_folio Kairui Song via B4 Relay
2026-02-19 23:42 ` [PATCH RFC 03/15] mm, swap: move conflict checking logic of out swap cache adding Kairui Song via B4 Relay
2026-02-19 23:42 ` [PATCH RFC 04/15] mm, swap: add support for large order folios in swap cache directly Kairui Song via B4 Relay
2026-02-19 23:42 ` [PATCH RFC 05/15] mm, swap: unify large folio allocation Kairui Song via B4 Relay
2026-02-19 23:42 ` [PATCH RFC 06/15] memcg, swap: reparent the swap entry on swapin if swapout cgroup is dead Kairui Song via B4 Relay
2026-02-23 16:22 ` Johannes Weiner
2026-02-24 5:44 ` Shakeel Butt
2026-02-24 8:08 ` Kairui Song
2026-02-19 23:42 ` [PATCH RFC 07/15] memcg, swap: defer the recording of memcg info and reparent flexibly Kairui Song via B4 Relay
2026-02-19 23:42 ` [PATCH RFC 08/15] mm, swap: store and check memcg info in the swap table Kairui Song via B4 Relay
2026-02-23 16:36 ` Johannes Weiner
2026-02-24 8:34 ` Kairui Song
2026-02-24 15:58 ` Johannes Weiner
2026-02-19 23:42 ` [PATCH RFC 09/15] mm, swap: support flexible batch freeing of slots in different memcg Kairui Song via B4 Relay
2026-02-19 23:42 ` [PATCH RFC 10/15] mm, swap: always retrieve memcg id from swap table Kairui Song via B4 Relay
2026-02-19 23:42 ` [PATCH RFC 11/15] mm/swap, memcg: remove swap cgroup array Kairui Song via B4 Relay
2026-02-19 23:42 ` [PATCH RFC 12/15] mm, swap: merge zeromap into swap table Kairui Song via B4 Relay
2026-02-25 12:19 ` Barry Song [this message]
2026-02-25 12:33 ` Kairui Song
2026-02-19 23:42 ` [PATCH RFC 13/15] mm: ghost swapfile support for zswap Kairui Song via B4 Relay
2026-02-19 23:42 ` [PATCH RFC 14/15] mm, swap: add a special device for ghost swap setup Kairui Song via B4 Relay
2026-02-19 23:42 ` [PATCH RFC 15/15] mm, swap: allocate cluster dynamically for ghost swapfile Kairui Song via B4 Relay
2026-02-21 8:15 ` [PATCH RFC 00/15] mm, swap: swap table phase IV with dynamic " Barry Song
2026-02-21 9:07 ` Kairui Song
2026-02-21 9:30 ` Barry Song
2026-02-23 16:52 ` Johannes Weiner
2026-02-24 2:10 ` Kairui Song
2026-02-23 18:22 ` Nhat Pham
2026-02-24 3:34 ` Kairui Song
2026-02-24 21:56 ` Nhat Pham
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