Abstract:
Provided are a computer program product, system, and method for managing data in a cache system comprising a first cache, a second cache, and a storage system. A determination is made of tracks stored in the storage system to demote from the first cache. A first stride is formed including the determined tracks to demote. A determination is made of a second stride in the second cache in which to include the tracks in the first stride. The tracks from the first stride are added to the second stride in the second cache. A determination is made of tracks in strides in the second cache to demote from the second cache. The determined tracks to demote from the second cache are demoted.
Abstract:
Copy-source-to-target-Operationen können selektiv und präemptiv vor Quellen-Auslagerungsoperationen vorgenommen werden. In einem weiteren Aspekt erkennt Logik sequenzielle Schreibvorgänge, zu denen Schreibvorgänge von großen Blöcken gehören, an Zeitpunktkopie-Quellen. Als Reaktion darauf werden Auslagerungstasks auf den zugehörigen Zeitpunktkopie-Zielen begonnen, die in einer Ausführungsform auf einen Stride ausgerichtete Copy-source-to-target-Operationen umfassen, die nicht geänderte Daten von den Zeitpunktkopie-Quellen an die Zeitpunktkopie-Ziele kopieren, die an den Strides des Ziels ausgerichtet sind. Somit, wenn Schreibdaten von Schreiboperationen an die Zeitpunktkopie-Quellen ausgelagert werden, brauchen solche Quellen-Auslagerungen nicht auf Copy-source-to-target-Operationen zu warten, da sie bereits durchgeführt worden sind. Ferner können die Copy-source-to-target-Operationen in Bezug auf die Stride-Begrenzungen der Zeitpunktkopie-Ziele auf einen Stride ausgerichtet sein. Weitere Merkmale und Aspekte können in Abhängigkeit von der jeweiligen Anwendung realisiert werden.
Abstract:
A determination is made of a unit of data, or track, to demote, castout, destage, writeback or evict from a first cache to a second cache, wherein the track in the first cache corresponds to a track in a storage system and is comprised of a plurality of sectors. In response to determining that the second cache includes the stale version of the track being demoted from the first cache, a determination is made as to whether the stale version of the track includes track sectors not included in the track being demoted from the first cache (i.e. if the first cache version of the track is a partial track and the second cache version is the whole track). The sectors from the track demoted from the first cache are combined with sectors from the stale version of the track not included in the track being demoted from the first cache into a new version of the track. The new version of the track is written to the second cache.
Abstract:
Bereitgestellt wird ein E/A-Gehäusemodul mit einem oder mehreren E/A-Gehäusen mit einer Vielzahl von Steckplätzen für die Aufnahme von Elektronikeinheiten. Ein Hostadapter ist mit einem ersten Steckplatz des E/A-Gehäusemoduls verbunden und so konfiguriert, dass er einen Host mit dem E/A-Gehäuse verbindet. Ein Einheitenadapter ist mit einem zweiten Steckplatz des E/A-Gehäusemoduls verbunden und so konfiguriert, dass er eine Speichereinheit mit dem E/A-Gehäusemodul verbindet. Ein Flash-Cache ist mit einem dritten Steckplatz des E/A-Gehäusemoduls verbunden und beinhaltet einen Flash-basierten Speicher, der so konfiguriert ist, dass er Daten zwischenspeichert, die Datenanforderungen zugehörig sind, welche durch das E/A-Gehäusemodul verarbeitet werden. Ein primärer Prozessorkomplex verwaltet Datenanforderungen, die durch das E/-A-Gehäusemodul verarbeitet werden, indem er mit dem Hostadapter, dem Einheitenadapter und dem Flash-Cache Daten austauscht, um die Datenanforderungen zu verwalten.
Abstract:
An I/O enclosure module is provided with one or more I/O enclosures having a plurality of slots for receiving electronic devices. A host adapter is connected a first slot of the I/O enclosure module and is configured to connect a host to the I/O enclosure. A device adapter is connected to a second slot of the I/O enclosure module and is configured to connect a storage device to the I/O enclosure module. A flash cache is connected to a third slot of the I/O enclosure module and includes a flash-based memory configured to cache data associated with data requests handled through the I/O enclosure module. A primary processor complex manages data requests handled through the I/O enclosure module by communicating with the host adapter, device adapter, and flash cache to manage to the data requests.
Abstract:
Provided are a method, system, and article of manufacture for determining modified data in cache for use during a recovery operation. An event is detected during which processing of writes to a storage device is suspended. A cache including modified data not destaged to the storage device is scanned to determine the data units having modified data in response to detecting the event. The data units having the modified data is indicated in a backup storage. The indication of the data units having the modified data in the backup storage is used during a recovery operation.
Abstract:
Verfahren, das umfasst:Schreiben eines geänderten Satzes von Daten für eine Zeitpunktkopie-Quelle (50) in einen Cache (28), wobei der geänderte Satz von Daten in Bezug auf einen nicht geänderten Satz von Daten in der Zeitpunktkopie-Quelle (50) geändert wird;Feststellen, ob Bedingungen für präemptive Copy-source-to-target-Operationen (410) für Daten vorhanden sind, die sich auf die geänderten Daten in dem Cache (28) beziehen; undals Reaktion auf eine Feststellung, dass Bedingungen für präemptive Copy-source-to-target-Operationen vorhanden sind, präemptives und selektives Einleiten einer Copy-source-to-target-Operation, die umfasst:Lesen (484) der Zeitpunktkopie-Quelle (50), um Lesedaten zu erhalten, die den nicht geänderten Satz von Daten enthalten; undSchreiben (488) des nicht geänderten Satzes von Daten an ein Zeitpunktkopie-Ziel (54); undEinleiten einer Durchsuchung des Cache (28), um Spuren von geänderten Daten in dem Cache zu kennzeichnen, die in den Speicher auszulagern sind.
Abstract:
A memory may contain a large number of bytes of data perhaps as many as 256 megabytes in a typical large memory structure. An error correcting code algorithm may be used to identify failing memory modules in a memory system. In a particular embodiment, a number of spares may be provided on each memory card allowing a predetermined number of defective array modules to be replaced in a storage word. With double bit correction provided by the error correcting code logic, a number of bits can be corrected on a card or a larger number of bits can be corrected on a card pair, where the larger number of bits is somewhat less than double the number of bits which can be corrected on a single card. The address test in accordance with the present invention then produces a pattern that will create a difference greater than that larger number of bits between the data stored in a storage location under test and any address that could be accessed by an address line failure. The method according to the present invention predicts the effect of an address line failure external to the array modules and internal to a card pair and then tests to see if a failure has occurred. The address test does not declare an address failure until a predetermined number of bit failures on a card is found. The test is valid for single and multiple address line failures. Since only one address bit is changed for each path through the test other failing address lines will not be detected until the path with those failing address bits are tested. Thus, even with multiple address line failure the two addresses that are stored to and fetched from are the only one address bit apart.
Abstract:
A memory may contain a large number of bytes of data perhaps as many as 256 megabytes in a typical large memory structure. An error correcting code algorithm may be used to identify failing memory modules in a memory system. In a particular embodiment, a number of spares may be provided on each memory card allowing a predetermined number of defective array modules to be replaced in a storage word. With double bit correction provided by the error correcting code logic, a number of bits can be corrected on a card or a larger number of bits can be corrected on a card pair, where the larger number of bits is somewhat less than double the number of bits which can be corrected on a single card. The address test in accordance with the present invention then produces a pattern that will create a difference greater than that larger number of bits between the data stored in a storage location under test and any address that could be accessed by an address line failure. The method according to the present invention predicts the effect of an address line failure external to the array modules and internal to a card pair and then tests to see if a failure has occurred. The address test does not declare an address failure until a predetermined number of bit failures on a card is found. The test is valid for single and multiple address line failures. Since only one address bit is changed for each path through the test other failing address lines will not be detected until the path with those failing address bits are tested. Thus, even with multiple address line failure the two addresses that are stored to and fetched from are the only one address bit apart.