Abstract: A method for obtaining information related to a filesystem path in a file system that is stored in a storage system, the method may include (i) receiving a request to obtain hierarchy information related to file system entities stored under the filesystem path; and (ii) retrieving the hierarchy information; wherein the retrieving comprises accessing a filesystem hierarchy table that stores information regarding pathnames of file system entities of the file system; wherein the retrieving includes searching for path components of the filesystem path in subsets of cells of the filesystem hierarchy table, wherein each subset of cells is part of a set of cells that include path components of a certain pathname of a filesystem entity that belong to the file system.

Abstract: A method for determining size information related one or more file systems stored in a storage system, the method may include (i) sampling one or more logical spaces that are associated with the one or more file systems to provide sampled file system entities (FSEs); wherein a number of samples per sampled FSE is indicative of a size of the sampled FSEs; and (ii) determining logical sizes and physical sizes of different levels of the one or more file systems based on the sampled file system entities.

Abstract: A method for receiving paths information of a file system (FS) that is stored in a storage system, the method includes (a) receiving a request to receive paths information of at least part of the FS; wherein the request is received at a request point in time (PIT); (b) determining a current path name information of the at least part of the FS, wherein the determining is based on: (i) a FS paths data structure that includes path name information that is updated up to a last update PIT, and (ii) FS paths change information that is indicative of FS path names changes introduced between the last update PIT and the request PIT; wherein the FS paths change information associates at least one of excluded FSEs and included FSEs for each direct or indirect ancestor FSE of any FSE that had its path name changed between the last update PIT and the request PIT; and (c) generating a response to the request, wherein the generating of the response comprises using the current FS path name information of the FS.

Abstract: A method for obtaining information related to a filesystem path in a file system that is stored in a storage system, the method may include (i) receiving a request to obtain hierarchy information related to file system entities stored under the filesystem path; and (ii) retrieving the hierarchy information; wherein the retrieving comprises accessing a filesystem hierarchy table that stores information regarding pathnames of file system entities of the file system; wherein the retrieving includes searching for path components of the filesystem path in subsets of cells of the filesystem hierarchy table, wherein each subset of cells is part of a set of cells that include path components of a certain pathname of a filesystem entity that belong to the file system.

Abstract: A method for monitoring a storage system, the method may include (a) generating a compute entity (CE) storage metric by each CE of a group of CEs to provide multiple CE storage metrics, wherein the multiple CE metrics are related to a monitoring period; and (b) calculating, during a calculation period, a group metric based on the multiple CE storage metrices; wherein the calculating includes performing multiple calculations iterations, wherein each calculation iteration includes (a) selecting an updating CE that belongs to the group of CEs and was not previously selected during the calculation period, (b) accessing, by the updating CE, a shared data structure that stores the group storage metric, and (c) updating the group storage metric using the CE storage metric of the updating CE.

Abstract: A method for determining size information related one or more snapshots related to file systems stored in a storage system, the method may include (a) sampling one or more combinations of points in time and logical spaces, the logical spaces are associated with the one or more file systems to provide sampled combinations of sampled portions of file system entities (FSEs) and sampled points in time; (b) searching for relevant snapshots that are relevant to the sampled combinations to provide relevant snapshots at the sampled points in time; and (c) determining physical sizes of the relevant snapshots at the sampled point in time; wherein a number of samples per sampled FSE is indicative of a size of the sampled FSEs.

Abstract: A method for determining size information related one or more file systems stored in a storage system, the method may include (i) sampling one or more logical spaces that are associated with the one or more file systems to provide sampled file system entities (FSEs); wherein a number of samples per sampled FSE is indicative of a size of the sampled FSEs; and (ii) determining logical sizes and physical sizes of different levels of the one or more file systems based on the sampled file system entities.

Abstract: A method for determining size information related one or more snapshots related to file systems stored in a storage system, the method may include (a) sampling one or more combinations of points in time and logical spaces, the logical spaces are associated with the one or more file systems to provide sampled combinations of sampled portions of file system entities (FSEs) and sampled points in time; (b) searching for relevant snapshots that are relevant to the sampled combinations to provide relevant snapshots at the sampled points in time; and (c) determining physical sizes of the relevant snapshots at the sampled point in time; wherein a number of samples per sampled FSE is indicative of a size of the sampled FSEs

Abstract: A method for monitoring a storage system, the method may include (a) generating a compute entity (CE) storage metric by each CE of a group of CEs to provide multiple CE storage metrics, wherein the multiple CE metrics are related to a monitoring period; and (b) calculating, during a calculation period, a group metric based on the multiple CE storage metrices; wherein the calculating includes performing multiple calculations iterations, wherein each calculation iteration includes (a) selecting an updating CE that belongs to the group of CEs and was not previously selected during the calculation period, (b) accessing, by the updating CE, a shared data structure that stores the group storage metric, and (c) updating the group storage metric using the CE storage metric of the updating CE.

Abstract: A method for low-latency data mirroring in a storage system, the method may include receiving, by a compute node of the storage system, a read request for reading a data unit stored at a primary storage block of the storage system; determining, by the compute node and based on primary storage block metadata, whether a content of the primary storage block is consistent; and responding to the determining of whether the content of the primary storage block is consistent. The responding may include (a) when determining that the primary storage block is inconsistent—copying the data unit from the primary storage block to a secondary storage block of the storage system, and updating the primary storage block metadata; and (b) reading the data unit from the primary storage block and sending the data unit to a requesting entity.

Abstract: A method for low-latency data mirroring in a storage system, the method may include receiving, by a compute node of the storage system, a read request for reading a data unit stored at a primary storage block of the storage system; determining, by the compute node and based on primary storage block metadata, whether a content of the primary storage block is consistent; and responding to the determining of whether the content of the primary storage block is consistent. The responding may include (a) when determining that the primary storage block is inconsistent—copying the data unit from the primary storage block to a secondary storage block of the storage system, and updating the primary storage block metadata; and (b) reading the data unit from the primary storage block and sending the data unit to a requesting entity.