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charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: epam.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: VI1PR03MB3710.eurprd03.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3d2ec12a-8848-48a2-8fc8-08dbb91dbef1 X-MS-Exchange-CrossTenant-originalarrivaltime: 19 Sep 2023 14:36:01.1346 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: b41b72d0-4e9f-4c26-8a69-f949f367c91d X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: SfMGMyGOccD/w3BjjqL8MW9F/GjCuw0W07Hb22srLnjXMogouEJH2OIW/x49mI96wUKrBqCJJxkq+ZCo1JECS/x+c6qQWIvmtfMhJ26IlJA= X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR03MB6286 X-Proofpoint-GUID: o8keAZ_xJ1dGjwaxvH4rjiKqi_0kMkB- X-Proofpoint-ORIG-GUID: o8keAZ_xJ1dGjwaxvH4rjiKqi_0kMkB- X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.980,Hydra:6.0.601,FMLib:17.11.176.26 definitions=2023-09-19_06,2023-09-19_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1015 lowpriorityscore=0 phishscore=0 mlxlogscore=569 mlxscore=0 suspectscore=0 bulkscore=0 priorityscore=1501 adultscore=0 malwarescore=0 impostorscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2308100000 definitions=main-2309190125 Hi Julien, Julien Grall writes: > Hi Volodymyr, > > On 19/09/2023 12:28, Volodymyr Babchuk wrote: >> There is no need to invalidate cache entry because we just wrote into a >> memory region. Writing itself guarantees that cache entry is valid. > > The goal of invalidate is to remove the line from the cache. So I > don't quite understand the reasoning here. > Well, I may be wrong, but what is the goal in removing line from the cache? As I see this, we want to be sure that ITS sees data written in the memory, so we should flush a cache line. But why do we need to remove it from CPU's cache? --=20 WBR, Volodymyr=