Received: from localhost (unknown [200.46.204.183]) by developer.postgresql.org (Postfix) with ESMTP id 5BAA22E0127 for ; Thu, 15 May 2008 03:14:25 -0300 (ADT) Received: from developer.postgresql.org ([200.46.204.71]) by localhost (mx1.hub.org [200.46.204.183]) (amavisd-maia, port 10024) with ESMTP id 65379-07 for ; Thu, 15 May 2008 03:13:45 -0300 (ADT) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from service-web.de (p15093784.pureserver.info [217.160.106.224]) by developer.postgresql.org (Postfix) with ESMTP id 1A0302E00B7 for ; Thu, 15 May 2008 02:20:27 -0300 (ADT) Received: from [145.228.94.72] (unknown [145.228.94.72]) by service-web.de (Postfix) with ESMTP id 33DD3E8138; Thu, 15 May 2008 07:20:21 +0200 (CEST) Message-ID: <482BC80B.3010109@wildenhain.de> Date: Thu, 15 May 2008 07:20:11 +0200 From: Tino Wildenhain User-Agent: Thunderbird 2.0.0.14 (Windows/20080421) MIME-Version: 1.0 To: Luke Lonergan Cc: Pavan Deolasee , Greg Smith , Alvaro Herrera , pgsql-performance@postgresql.org Subject: Re: I/O on select count(*) References: In-Reply-To: Content-Type: multipart/signed; protocol="application/x-pkcs7-signature"; micalg=sha1; boundary="------------ms010109000703010000020904" X-Virus-Scanned: Maia Mailguard 1.0.1 X-Archive-Number: 200805/197 X-Sequence-Number: 30165 This is a cryptographically signed message in MIME format. --------------ms010109000703010000020904 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: quoted-printable Hi, Luke Lonergan wrote: > BTW =96 we=92ve removed HINT bit checking in Greenplum DB and improved = the=20 > visibility caching which was enough to provide performance at the same = > level as with the HINT bit optimization, but avoids this whole =93write= =20 > the data, write it to the log also, then write it again just for good=20 > measure=94 behavior. can you go a bit deeper into how you implemented this or is it some IP of greenplum you cannot reveal? Btw, is there something with your eyes: ? :-)) Cheers Tino --------------ms010109000703010000020904 Content-Type: application/x-pkcs7-signature; name="smime.p7s" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="smime.p7s" Content-Description: S/MIME Cryptographic Signature MIAGCSqGSIb3DQEHAqCAMIACAQExCzAJBgUrDgMCGgUAMIAGCSqGSIb3DQEHAQAAoIIJBzCC At4wggJHoAMCAQICEFhzOX0yh1CxCcTpCoXqqXkwDQYJKoZIhvcNAQEFBQAwYjELMAkGA1UE BhMCWkExJTAjBgNVBAoTHFRoYXd0ZSBDb25zdWx0aW5nIChQdHkpIEx0ZC4xLDAqBgNVBAMT I1RoYXd0ZSBQZXJzb25hbCBGcmVlbWFpbCBJc3N1aW5nIENBMB4XDTA4MDQzMDE5MzY1NFoX DTA5MDQzMDE5MzY1NFowRDEfMB0GA1UEAxMWVGhhd3RlIEZyZWVtYWlsIE1lbWJlcjEhMB8G CSqGSIb3DQEJARYSdGlub0B3aWxkZW5oYWluLmRlMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8A MIIBCgKCAQEAwdJKlg6wlxFdjMOMON992A1RRg7jfZJWPuHXAb0VOAM4htilnwfJVdk9ARnY Jbp6uDbR7Npm3ZqrqfRlI2uPXVVj00L8JHMQmeS36ICknk7aG93yTBYWBf1T2EadP2KFszSM EmfjxV7vc55BgP1Pj9eB0ceJOT8dOWl5c342giavCWOg0xDQAKUd+BpEe3r/TnLuCUo0MIQF DAO8nw8NyKJG82u0Y8aHW5wpLS0S0E+GeVd5RP4cB1GDCiH8Bi7MvOSsFBv7tSYIn/3fJH+Q 979UGd1nhO4H+sK43mjt+gXpR7+5A3ZGy+O/5gsArCTMwGZmLZ4hd3VhPCT7TRtLmQIDAQAB oy8wLTAdBgNVHREEFjAUgRJ0aW5vQHdpbGRlbmhhaW4uZGUwDAYDVR0TAQH/BAIwADANBgkq hkiG9w0BAQUFAAOBgQA3ROUGts7nkRx1uE+rbeuhfckv9bLIL6lz19tRwTeTOYanXrqDzwhn UUMyd7oDFUIZe/lxtLshkUD4p/omXtIzCCx6M5yIWlYMzKTeB4qQpQ14huovXzXQZbWiTOwA 3+ZU+rVC7CX47dEEKuKHwAvpurNUGikHlGuYkMSMCly61zCCAt4wggJHoAMCAQICEFhzOX0y h1CxCcTpCoXqqXkwDQYJKoZIhvcNAQEFBQAwYjELMAkGA1UEBhMCWkExJTAjBgNVBAoTHFRo YXd0ZSBDb25zdWx0aW5nIChQdHkpIEx0ZC4xLDAqBgNVBAMTI1RoYXd0ZSBQZXJzb25hbCBG cmVlbWFpbCBJc3N1aW5nIENBMB4XDTA4MDQzMDE5MzY1NFoXDTA5MDQzMDE5MzY1NFowRDEf MB0GA1UEAxMWVGhhd3RlIEZyZWVtYWlsIE1lbWJlcjEhMB8GCSqGSIb3DQEJARYSdGlub0B3 aWxkZW5oYWluLmRlMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAwdJKlg6wlxFd jMOMON992A1RRg7jfZJWPuHXAb0VOAM4htilnwfJVdk9ARnYJbp6uDbR7Npm3ZqrqfRlI2uP XVVj00L8JHMQmeS36ICknk7aG93yTBYWBf1T2EadP2KFszSMEmfjxV7vc55BgP1Pj9eB0ceJ OT8dOWl5c342giavCWOg0xDQAKUd+BpEe3r/TnLuCUo0MIQFDAO8nw8NyKJG82u0Y8aHW5wp LS0S0E+GeVd5RP4cB1GDCiH8Bi7MvOSsFBv7tSYIn/3fJH+Q979UGd1nhO4H+sK43mjt+gXp R7+5A3ZGy+O/5gsArCTMwGZmLZ4hd3VhPCT7TRtLmQIDAQABoy8wLTAdBgNVHREEFjAUgRJ0 aW5vQHdpbGRlbmhhaW4uZGUwDAYDVR0TAQH/BAIwADANBgkqhkiG9w0BAQUFAAOBgQA3ROUG ts7nkRx1uE+rbeuhfckv9bLIL6lz19tRwTeTOYanXrqDzwhnUUMyd7oDFUIZe/lxtLshkUD4 p/omXtIzCCx6M5yIWlYMzKTeB4qQpQ14huovXzXQZbWiTOwA3+ZU+rVC7CX47dEEKuKHwAvp urNUGikHlGuYkMSMCly61zCCAz8wggKooAMCAQICAQ0wDQYJKoZIhvcNAQEFBQAwgdExCzAJ BgNVBAYTAlpBMRUwEwYDVQQIEwxXZXN0ZXJuIENhcGUxEjAQBgNVBAcTCUNhcGUgVG93bjEa MBgGA1UEChMRVGhhd3RlIENvbnN1bHRpbmcxKDAmBgNVBAsTH0NlcnRpZmljYXRpb24gU2Vy dmljZXMgRGl2aXNpb24xJDAiBgNVBAMTG1RoYXd0ZSBQZXJzb25hbCBGcmVlbWFpbCBDQTEr MCkGCSqGSIb3DQEJARYccGVyc29uYWwtZnJlZW1haWxAdGhhd3RlLmNvbTAeFw0wMzA3MTcw MDAwMDBaFw0xMzA3MTYyMzU5NTlaMGIxCzAJBgNVBAYTAlpBMSUwIwYDVQQKExxUaGF3dGUg Q29uc3VsdGluZyAoUHR5KSBMdGQuMSwwKgYDVQQDEyNUaGF3dGUgUGVyc29uYWwgRnJlZW1h aWwgSXNzdWluZyBDQTCBnzANBgkqhkiG9w0BAQEFAAOBjQAwgYkCgYEAxKY8VXNV+065ypla HmjAdQRwnd/p/6Me7L3N9VvyGna9fww6YfK/Uc4B1OVQCjDXAmNaLIkVcI7dyfArhVqqP3FW y688Cwfn8R+RNiQqE88r1fOCdz0Dviv+uxg+B79AgAJk16emu59l0cUqVIUPSAR/p7bRPGEE QB5kGXJgt/sCAwEAAaOBlDCBkTASBgNVHRMBAf8ECDAGAQH/AgEAMEMGA1UdHwQ8MDowOKA2 oDSGMmh0dHA6Ly9jcmwudGhhd3RlLmNvbS9UaGF3dGVQZXJzb25hbEZyZWVtYWlsQ0EuY3Js MAsGA1UdDwQEAwIBBjApBgNVHREEIjAgpB4wHDEaMBgGA1UEAxMRUHJpdmF0ZUxhYmVsMi0x MzgwDQYJKoZIhvcNAQEFBQADgYEASIzRUIPqCy7MDaNmrGcPf6+svsIXoUOWlJ1/TCG4+DYf qi2fNi/A9BxQIJNwPP2t4WFiw9k6GX6EsZkbAMUaC4J0niVQlGLH2ydxVyWN3amcOY6MIE9l X5Xa9/eH1sYITq726jTlEBpbNU1341YheILcIRk13iSx0x1G/11fZU8xggNkMIIDYAIBATB2 MGIxCzAJBgNVBAYTAlpBMSUwIwYDVQQKExxUaGF3dGUgQ29uc3VsdGluZyAoUHR5KSBMdGQu MSwwKgYDVQQDEyNUaGF3dGUgUGVyc29uYWwgRnJlZW1haWwgSXNzdWluZyBDQQIQWHM5fTKH ULEJxOkKheqpeTAJBgUrDgMCGgUAoIIBwzAYBgkqhkiG9w0BCQMxCwYJKoZIhvcNAQcBMBwG CSqGSIb3DQEJBTEPFw0wODA1MTUwNTIwMTFaMCMGCSqGSIb3DQEJBDEWBBQJZyRTpXnlmcA0 sVAHvG7EEG/LyDBSBgkqhkiG9w0BCQ8xRTBDMAoGCCqGSIb3DQMHMA4GCCqGSIb3DQMCAgIA gDANBggqhkiG9w0DAgIBQDAHBgUrDgMCBzANBggqhkiG9w0DAgIBKDCBhQYJKwYBBAGCNxAE MXgwdjBiMQswCQYDVQQGEwJaQTElMCMGA1UEChMcVGhhd3RlIENvbnN1bHRpbmcgKFB0eSkg THRkLjEsMCoGA1UEAxMjVGhhd3RlIFBlcnNvbmFsIEZyZWVtYWlsIElzc3VpbmcgQ0ECEFhz OX0yh1CxCcTpCoXqqXkwgYcGCyqGSIb3DQEJEAILMXigdjBiMQswCQYDVQQGEwJaQTElMCMG A1UEChMcVGhhd3RlIENvbnN1bHRpbmcgKFB0eSkgTHRkLjEsMCoGA1UEAxMjVGhhd3RlIFBl cnNvbmFsIEZyZWVtYWlsIElzc3VpbmcgQ0ECEFhzOX0yh1CxCcTpCoXqqXkwDQYJKoZIhvcN AQEBBQAEggEAQLAFCSXzzN6jIF7m/voZYat2K5O2eXXWmICZyM+p6yi4SaOSwbwdUsT3EYJ5 n13xvFuW07Wd7Te+GcVejw7FrQ6uyxJTEqPRhwp5PfCgh1G0dBYCtRqAyyVLI1GJllBSYRWf tZCSAxUEyC8oEirEwjcO2NMvydIqla3M0hYImLNkmiEv5q6JOiJhdICyFbGwwhIXstJoAjn0 ipDfWWTm9wGtA8HTGl++glJuuDS+fixZeGvF62vCz6DIUvJtKi+w4rI3QKKlQPsMN7OJ4Ihn 61XZLIbceevZR5Nu2kVd/M+F1IMy+NCd9S1d88nFPyWndx+qQRUAWJdmAqOATS3mPwAAAAAA AA== --------------ms010109000703010000020904--