From users-return-268700-archive-asf-public=cust-asf.ponee.io@tomcat.apache.org Thu Nov 7 11:40:33 2019 Return-Path: X-Original-To: archive-asf-public@cust-asf.ponee.io Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [207.244.88.153]) by mx-eu-01.ponee.io (Postfix) with SMTP id 44B2E180630 for ; Thu, 7 Nov 2019 12:40:33 +0100 (CET) Received: (qmail 38940 invoked by uid 500); 7 Nov 2019 11:40:29 -0000 Mailing-List: contact users-help@tomcat.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: "Tomcat Users List" Delivered-To: mailing list users@tomcat.apache.org Received: (qmail 38928 invoked by uid 99); 7 Nov 2019 11:40:29 -0000 Received: from Unknown (HELO mailrelay1-lw-us.apache.org) (10.10.3.42) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 07 Nov 2019 11:40:29 +0000 Received: from [192.168.23.12] (host213-121-9-136.range213-121.btcentralplus.com [213.121.9.136]) by mailrelay1-lw-us.apache.org (ASF Mail Server at mailrelay1-lw-us.apache.org) with ESMTPSA id 191DA1003 for ; Thu, 7 Nov 2019 11:40:28 +0000 (UTC) Subject: Re: Intermittent JSP Caching/Compiling Issue while under load To: users@tomcat.apache.org References: <420900e0-5097-0881-edea-c9ba175ea99b@apache.org> <9a7fd033-27fc-6ca2-b3e9-56989accf09d@apache.org> <0d006b48-e212-944c-9cfd-2a28c695f496@apache.org> <3098c3af-3c30-02a5-573f-ead9ea65a47e@apache.org> From: Mark Thomas Openpgp: preference=signencrypt Autocrypt: addr=markt@apache.org; prefer-encrypt=mutual; keydata= mQINBEq0DukBEAD4jovHOPJDxoD+JnO1Go2kiwpgRULasGlrVKuSUdP6wzcaqWmXpqtOJKKw W2MQFQLmg7nQ9RjJwy3QCbKNDJQA/bwbQT1F7WzTCz2S6vxC4zxKck4t6RZBq2dJsYKF0CEh 6ZfY4dmKvhq+3istSoFRdHYoOPGWZpuRDqfZPdGm/m335/6KGH59oysn1NE7a2a+kZzjBSEg v23+l4Z1Rg7+fpz1JcdHSdC2Z+ZRxML25eVatRVz4yvDOZItqDURP24zWOodxgboldV6Y88C 3v/7KRR+1vklzkuA2FqF8Q4r/2f0su7MUVviQcy29y/RlLSDTTYoVlCZ1ni14qFU7Hpw43KJ tgXmcUwq31T1+SlXdYjNJ1aFkUi8BjCHDcSgE/IReKUanjHzm4XSymKDTeqqzidi4k6PDD4j yHb8k8vxi6qT6Udnlcfo5NBkkUT1TauhEy8ktHhbl9k60BvvMBP9l6cURiJg1WS77egI4P/8 2oPbzzFiGFqXyJKULVgxtdQ3JikCpodp3f1fh6PlYZwkW4xCJLJucJ5MiQp07HAkMVW5w+k8 Xvuk4i5quh3N+2kzKHOOiQCDmN0sz0XjOE+7XBvM1lvz3+UarLfgSVmW8aheLd7eaIl5ItBk 8844ZJ60LrQ+JiIqvqJemxyIM6epoZvY5a3ZshZpcLilC5hW8QARAQABtCJNYXJrIEUgRCBU aG9tYXMgPG1hcmt0QGFwYWNoZS5vcmc+iQI3BBMBCgAhBQJKtA7pAhsDBQsJCAcDBRUKCQgL BRYCAwEAAh4BAheAAAoJEBDAHFovYFnn2YgQAKN6FLG/I1Ij3PUlC/XNlhasQxPeE3w2Ovtt weOQPYkblJ9nHtGH5pNqG2/qoGShlpI04jJy9GxWKOo7NV4v7M0mbVlCXVgjdlvMFWdL7lno cggwJAFejQcYlVtxyhu4m50LBvBunEhxCbQcKnnWmkB7Ocm0Ictaqjc9rCc1F/aNhVMUpJ0z G1kyTp9hxvN6TbCQlacMx5ocTWzL0zn6QZhbUfrYwfxYJmSnkVYZOYzXIXIsLN5sJ9Q4P8tj Y4qWgd+bQvOqPWrkzL9LVRnGOrSYIsoM5zWdoj1g1glMzK/ZqJdRqqqBhe6FYTbXipz8oX8i mCebcaxZnfLhGiqqX+yDa3YUwDiqom+sZOc0iXGvKkqltPLpNeF0MVT7aZjalsQ/v2Ysb24R Ql9FfjfWmvT8ZPWz8Kore1AI4UcIIgFVtM+zuLlL9CIsGjg+gHDE2dhZDY0qfizlHL9CoAWU DM3pIfxM2V4BRn1xO+j/mModhjmYLZvnFVz4KGkNO7wRkofAANIWYo3WI5x83BGDH371t3NR rrpSSFP0XpQX6/Leaj2j6U6puABL2qBxhscsO6chc3u4/+019ff+peZVsc9ttcTQXsKIujmM b8p2sk5usmv6PKVX3oW/RAxpbVHU5kZ5px1Hq7mMQdZfLs5ff4YymXBH02z4/RmSzPam0Xb5 uQINBEq0DukBEADCNEkws5YroBmbu8789Xf006gTl5LzD/Hdt3sAp9iCfPgucO+l7U+xbo1X HTMJQwEVfS+Rx3RbaLYRG+hU7FuJLQB/5NaCDNRuqw5KHyQtJUH+zo84IqqfMzG8aOSdHg1y r2xKH4QTmgQONBu/W0xEZmZro6TjYNwkk2pwXK2yuImZPUOy+mK1qF8Wm3hTtkPE+FFSNFIa eHDoTGmx/0Riu/K7dNJTrC0TlRpn2K6d60zB53YYTc+0DYSDyB0FupXiAx/+XEGn3Q7eNi2B V6w50v5r51QP8zptiFflMfFKNAfV8xS5MteQd98YS5qqd/LPo3gS5HFPQaSL0k3RTClv7fQN HcZFqmv0OWpix6zm2npYxhqsTDGeSa52/uXehVXF5JubYFifMSLpbGVZqdrmG5hr2cycxsjF iY0zJOaRitmN/JWbOGLiwrcN4ukKNyFntFG5jPaFnJdx9rHfyJNeF9cgv9JlZeFxJ6WqIAhl KOuH3K8/py0SPE6ZOFfRo0YUxvh25K/siOcPLm613aOxyY7YfQ8ME2vgn7I0mAtg9am+YFDa bGqj839odwZdzZv2T2mUHnybFTJFBuMWGWKYstYDS6eZEmhupbPvUKkDug/mO+gdo+pSKF9Y S6DM5RtCdTNJq4NZY50ypBb5RSj+INHPocIp2V/DDTbzySsu6wARAQABiQIfBBgBCgAJBQJK tA7pAhsMAAoJEBDAHFovYFnnLe0P/i34oK5cE2LlqUEITEcTO94x1EX0UmtKokRfQ3AYWK8X eFD8cmSty72hMkL+1c0V//4Qc53SUyLIWXk8FKWF7hdL3zyuBqlRb55721CYC35GA/jR90p0 k1vr701gaat2cNTOVC0/6H9cE5yYXT+zMr9TSiKCDwONhhSbmAJZc6X0fgsmCD7I5xUI5Vri hN/Wx0CZBtrXGUyE4hgFaYSGptZmkY5Ln1e+nI185Bda7bpLwcAIGrI9nYtVXgf71ybGKdPP tFfXIoPXuctn99M7NnWBhNuGDms2YWkOC7eeWBTxKkZDWR3vRmRy52B6GxR7USk/KXs7yqGP kfT/c4CZFfOurZUXXuC3PvOme0DQmqwExtJormoG4Fy6suEFPrfhYMigTy7kSbVTCOBMjQLH +U/FFNshvg9+M/ZvaKT+0lpRvBSuG5ngsC0bO0xWsXhb6qfH2h53g4VcwFvCBL5IfqgAeUbC nGGHNcGWpmwdeb7D7ahrNZSHEUUYR7lTbjkYS01/QDOcEwNZOqDRIJUQOOUq35721VeROkdh ZmMZtFlsQeQJsWoqGrQo/kEYicVlMVOgjmOOzOa5fRb/IqlGlBn4a4me3hWthLLtMy+OOEim 6ENjntVTBQiTP/YqrxWDbCkaD7b2e9wY5N3JlRxMIQHfcHaND3PRdQSn7oHYXmJl Message-ID: Date: Thu, 7 Nov 2019 11:40:26 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit On 06/11/2019 20:04, Mark Thomas wrote: > I've found the root cause. > > When checking the timestamps of JSPs, the JSP engine (because it has to > access all resources via the Servlet API) requests a URL for the JSP, > opens a connection to the URL and then checks the last modified time. > This goes directly to the on-disk file. > > When reading the content, the request goes via the static resource cache > because we can intercept the call to ServletContext.getResourceAsStream() > > The problem is the following sequence: > - request for JSP > - no change in JSP timestamp found > - cache re-validated (for 5s by default) > - JSP is modified (within 5s) > - request for JSP (within 5s) > - change in JSP timestamp found > - JSP content read (sees cached version rather than new version) > > So we end up with the old version of the JSP content with the updated > last modification time. > > I'm currently looking at options to return a URL for the resource where > we can intercept the call to URLConnection.getLastModified(). Fixed in: - master for 9.0.28 onwards - 8.5.x for 8.5.48 onwards Mark --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org For additional commands, e-mail: users-help@tomcat.apache.org