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[207.229.128.216]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-8ccf623d1f4sm47553706d6.22.2026.05.31.18.49.47 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 31 May 2026 18:49:47 -0700 (PDT) Message-ID: Date: Sun, 31 May 2026 20:49:47 -0500 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Possible G2-item at SERIALIZABLE To: Andrey Borodin Cc: PostgreSQL mailing lists References: <165342c0-0c75-461e-b334-b997639ad48d@aphyr.com> <84AC98E5-3387-40A5-A258-C6E354349154@yandex-team.ru> Content-Language: en-US From: Kyle Kingsbury In-Reply-To: <84AC98E5-3387-40A5-A258-C6E354349154@yandex-team.ru> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk On 5/31/26 08:19, Andrey Borodin wrote: > Could you confirm whether you still observe G2-item anomalies with a server > configured default_transaction_isolation = 'serializable' (so that the > single-statement operations are certainly Serializable)? If they persist under that > setting I'll dig further... Yes, this was it, thank you. I've been reworking a whole bunch of things to make these tests portable between DBs and totally lost the session-wide transaction isolation. This behavior disappears with: SET SESSION CHARACTERISTICS AS TRANSACTION ISOLATION LEVEL SERIALIZABLE; Thank you kindly, Andrey. :-) --Kyle