MIME-Version: 1.0
References: 
 <CAHGQGwFzNYroAxSoyJhqTU-pH=t4Ej6RyvhVmBZ91Exj_TPMMQ@mail.gmail.com>
 <CAA4eK1+CrQNqiPDKv1wYfdkbX0FARJoi1=0ioaAqkLzbq2vG1w@mail.gmail.com>
 <CAHGQGwHABvuCoyM24HUiFZ5oJq_CoFomjt_cqD-0cJLMjFXJjQ@mail.gmail.com>
 <CAA4eK1LzZGfRANPAnv6NpKCH2ENuZO6HswgY14A=xsOXmucPhw@mail.gmail.com>
 <CABdArM6nepct0uxizCnZqy-kAjjTOndvu7bWtaNcmknuxx82Hg@mail.gmail.com>
 <CAJpy0uBhJB4HqouLXegD=miSkZfZp86tTC2K0K6nf=bHCcsPLQ@mail.gmail.com>
 <CABdArM6Mfhk2+9TVR_D3cgfPWPfHDuZEg7MOc5KqULwt0OcQUg@mail.gmail.com>
 <CAA4eK1+d2vN80-Yvy_Hr=ATF3XL5db+_W-sXF=2Vxm+OFBO82w@mail.gmail.com>
 <CAA4eK1KxU4b53GUor41A55x+Bx-DdOaQ9g1DqURyRY2Cg-hhPQ@mail.gmail.com>
 <CABdArM6pmn5yFqiU33KTYBXYM=Vny2ULnJY_gqFbsMEdt+1dPA@mail.gmail.com>
 <CAHGQGwEsEjXbCthXb02=HScBW7C=BHmygv9SK1VGCcc-9bmTsw@mail.gmail.com>
 <CABdArM5rrhSmFvVL4C5LL0iea-R0HRtB=ZvD=ereoTDa1Tm=NA@mail.gmail.com>
 <CAJpy0uD5brcAOpM8+UGfpzrm4pu-vsSfQUT2zgmcKsXEb8++4Q@mail.gmail.com>
 <CABdArM6E2aBj0FUjr2870sZUQqc6mpV1xSM=sqUFd2tKbfUQHA@mail.gmail.com>
 <TY4PR01MB16907318494FF276465E97DF79453A@TY4PR01MB16907.jpnprd01.prod.outlook.com>
 <CABdArM5RqLna+Y3CF=0BKew-WyxoAKXgcaOnXG1DZpMEiogCqw@mail.gmail.com>
 <CAHGQGwF1=zu478YX1kNaX+qaNp9DH_p+5ZdSfFdTa=JuynJufQ@mail.gmail.com>
 <CABdArM7OsLhyactNNUZ+Wygc_ybv4hhgje9c+h+=PHm3QdS4iQ@mail.gmail.com>
 <CAHGQGwHndKa--mCKAaSpAtdTte_3RJkUueZcDSqdUASqTsDK0Q@mail.gmail.com>
 <CAA4eK1JwVewYZc7eyF9x2-G+Y1ikgU5+a5gmQR+ssft++V51ZA@mail.gmail.com>
 <CAHGQGwHo8f+d3wF-beh6fQnftAkJUyd4mLm2Kg_m41Dg+6dCQQ@mail.gmail.com>
 <CAA4eK1Kb_-zVDcoTP34FZjYcgXAHkUu-vmmGYtH5Tg0o+jW_mQ@mail.gmail.com>
 <CAHGQGwGprr+1ycMFpkni4fOM=CGt7iO1yGnJROHqU59sewV0-Q@mail.gmail.com>
 <CAHGQGwH_AAbtsiYDJt65N7_4PJ0CgOJmBEaCq68e5_tcuG_vXw@mail.gmail.com>
In-Reply-To: 
 <CAHGQGwH_AAbtsiYDJt65N7_4PJ0CgOJmBEaCq68e5_tcuG_vXw@mail.gmail.com>
From: Fujii Masao <masao.fujii@gmail.com>
Date: Wed, 8 Apr 2026 15:54:10 +0900
Message-ID: 
 <CAHGQGwF7QvpRZL6sT3m5EeuacL4SePqmMu1+zJiJc3V2u-tBOA@mail.gmail.com>
Subject: Re: Use SIGTERM instead of SIGUSR1 for slotsync worker to exit during
 promotion?
To: Amit Kapila <amit.kapila16@gmail.com>
Cc: Nisha Moond <nisha.moond412@gmail.com>,
	"Zhijie Hou (Fujitsu)" <houzj.fnst@fujitsu.com>,
 shveta malik <shveta.malik@gmail.com>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Content-Type: multipart/mixed; boundary="000000000000b9e295064eed5e91"
Archived-At: 
 <https://www.postgresql.org/message-id/CAHGQGwF7QvpRZL6sT3m5EeuacL4SePqmMu1%2BzJiJc3V2u-tBOA%40mail.gmail.com>
Precedence: bulk

--000000000000b9e295064eed5e91
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Wed, Apr 8, 2026 at 12:36=E2=80=AFPM Fujii Masao <masao.fujii@gmail.com>=
 wrote:
> The backpatch added PROCSIG_SLOTSYNC_MESSAGE in the middle of enum
> ProcSignalReason, which could break the ABI. I=E2=80=99m planning to move=
 it to
> the end of the enum in v17 and v18.
>
> That seems to work for v18. However, in v17, NUM_PROCSIGNALS is defined
> as the last enum value:
>
>             NUM_PROCSIGNALS /* Must be last! */
>         } ProcSignalReason;
>
> So simply moving PROCSIG_SLOTSYNC_MESSAGE to the end would change the mea=
ning
> of NUM_PROCSIGNALS.
>
> One option might be to remove NUM_PROCSIGNALS from the enum, move
> PROCSIG_SLOTSYNC_MESSAGE to the end, and define it separately, e.g.
> #define NUM_PROCSIGNALS (PROCSIG_SLOTSYNC_MESSAGE + 1). Would that
> be acceptable without breaking the ABI? Thoughts?

The patches I'm planning to apply for v17 and v18 are attached.

For v17, I'm still not entirely sure this change is safe from an ABI
perspective. Even if it is, abi-compliance-check may still report
a break since the patch removes NUM_PROCSIGNALS from the enum
(defines it as separate macro). If so, we may need to update
.abi-compliance-history to avoid false positives.

Regards,

--=20
Fujii Masao

--000000000000b9e295064eed5e91
Content-Type: application/octet-stream;
	name="v1-0001-pg17-Fix-ABI-break-by-moving-PROCSIG_SLOTSYNC_MESSAGE-.patch"
Content-Disposition: attachment;
	filename="v1-0001-pg17-Fix-ABI-break-by-moving-PROCSIG_SLOTSYNC_MESSAGE-.patch"
Content-Transfer-Encoding: base64
Content-ID: <f_mnpozhqp0>
X-Attachment-Id: f_mnpozhqp0

RnJvbSBkNmFkNDg0N2RkYmVkZWFmYWQ2ODI2NTNkMzBlYWFmMGFkOGRlZGI3IE1vbiBTZXAgMTcg
MDA6MDA6MDAgMjAwMQpGcm9tOiBGdWppaSBNYXNhbyA8ZnVqaWlAcG9zdGdyZXNxbC5vcmc+CkRh
dGU6IFdlZCwgOCBBcHIgMjAyNiAxMjo1MzoyMyArMDkwMApTdWJqZWN0OiBbUEFUQ0ggdjFdIEZp
eCBBQkkgYnJlYWsgYnkgbW92aW5nIFBST0NTSUdfU0xPVFNZTkNfTUVTU0FHRSBpbgogUHJvY1Np
Z25hbFJlYXNvbgoKQ29tbWl0IDU4YzExODhhM2VhIGFkZGVkIFBST0NTSUdfU0xPVFNZTkNfTUVT
U0FHRSBpbiB0aGUgbWlkZGxlIG9mCmVudW0gUHJvY1NpZ25hbFJlYXNvbiwgYnJlYWtpbmcgdGhl
IEFCSS4KCkZpeCB0aGlzIGJ5IG1vdmluZyBQUk9DU0lHX1NMT1RTWU5DX01FU1NBR0UgdG8gdGhl
IGVuZCBvZiB0aGUgZW51bS4KClBlciBidWlsZGZhcm0gbWVtYmVyIGNyYWtlLgoKRGlzY3Vzc2lv
bjogaHR0cHM6Ly9wb3N0Z3IuZXMvbS9DQUhHUUd3SF9BQWJ0c2lZREp0NjVON180UEowQ2dPSm1C
RWFDcTY4ZTVfdGN1R192WHdAbWFpbC5nbWFpbC5jb20KLS0tCiBzcmMvaW5jbHVkZS9zdG9yYWdl
L3Byb2NzaWduYWwuaCB8IDUgKysrLS0KIDEgZmlsZSBjaGFuZ2VkLCAzIGluc2VydGlvbnMoKyks
IDIgZGVsZXRpb25zKC0pCgpkaWZmIC0tZ2l0IGEvc3JjL2luY2x1ZGUvc3RvcmFnZS9wcm9jc2ln
bmFsLmggYi9zcmMvaW5jbHVkZS9zdG9yYWdlL3Byb2NzaWduYWwuaAppbmRleCAxMjZjNDRiY2Yx
ZC4uZGI1OWQyNjZhMmMgMTAwNjQ0Ci0tLSBhL3NyYy9pbmNsdWRlL3N0b3JhZ2UvcHJvY3NpZ25h
bC5oCisrKyBiL3NyYy9pbmNsdWRlL3N0b3JhZ2UvcHJvY3NpZ25hbC5oCkBAIC0zNiw3ICszNiw2
IEBAIHR5cGVkZWYgZW51bQogCVBST0NTSUdfQkFSUklFUiwJCQkvKiBnbG9iYWwgYmFycmllciBp
bnRlcnJ1cHQgICovCiAJUFJPQ1NJR19MT0dfTUVNT1JZX0NPTlRFWFQsIC8qIGFzayBiYWNrZW5k
IHRvIGxvZyB0aGUgbWVtb3J5IGNvbnRleHRzICovCiAJUFJPQ1NJR19QQVJBTExFTF9BUFBMWV9N
RVNTQUdFLCAvKiBNZXNzYWdlIGZyb20gcGFyYWxsZWwgYXBwbHkgd29ya2VycyAqLwotCVBST0NT
SUdfU0xPVFNZTkNfTUVTU0FHRSwJLyogYXNrIHNsb3Qgc3luY2hyb25pemF0aW9uIHRvIHN0b3Ag
Ki8KIAogCS8qIFJlY292ZXJ5IGNvbmZsaWN0IHJlYXNvbnMgKi8KIAlQUk9DU0lHX1JFQ09WRVJZ
X0NPTkZMSUNUX0ZJUlNULApAQCAtNDksOSArNDgsMTEgQEAgdHlwZWRlZiBlbnVtCiAJUFJPQ1NJ
R19SRUNPVkVSWV9DT05GTElDVF9TVEFSVFVQX0RFQURMT0NLLAogCVBST0NTSUdfUkVDT1ZFUllf
Q09ORkxJQ1RfTEFTVCA9IFBST0NTSUdfUkVDT1ZFUllfQ09ORkxJQ1RfU1RBUlRVUF9ERUFETE9D
SywKIAotCU5VTV9QUk9DU0lHTkFMUwkJCQkvKiBNdXN0IGJlIGxhc3QhICovCisJUFJPQ1NJR19T
TE9UU1lOQ19NRVNTQUdFCS8qIGFzayBzbG90IHN5bmNocm9uaXphdGlvbiB0byBzdG9wICovCiB9
IFByb2NTaWduYWxSZWFzb247CiAKKyNkZWZpbmUgTlVNX1BST0NTSUdOQUxTIChQUk9DU0lHX1NM
T1RTWU5DX01FU1NBR0UgKyAxKQorCiB0eXBlZGVmIGVudW0KIHsKIAlQUk9DU0lHTkFMX0JBUlJJ
RVJfU01HUlJFTEVBU0UsIC8qIGFzayBzbWdyIHRvIGNsb3NlIGZpbGVzICovCi0tIAoyLjUxLjIK
Cg==
--000000000000b9e295064eed5e91
Content-Type: application/octet-stream;
	name="v1-0001-pg18-Fix-ABI-break-by-moving-PROCSIG_SLOTSYNC_MESSAGE-.patch"
Content-Disposition: attachment;
	filename="v1-0001-pg18-Fix-ABI-break-by-moving-PROCSIG_SLOTSYNC_MESSAGE-.patch"
Content-Transfer-Encoding: base64
Content-ID: <f_mnpozhr81>
X-Attachment-Id: f_mnpozhr81
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==
--000000000000b9e295064eed5e91--