Patents

US20180052904A1 Matching a first collection of strings with a second collection of strings

Inventors: Francesco Fusco, Yves G. Ineichen, Michel F. Speiser
Assignee: International Business Machines Corp
Status: Application

A method for matching first elements with second elements. Each of the first elements and second elements is a character string. The method comprises: calculating a first integer hash value for each of the first elements using a string hash function, wherein the first integer hash value is an output integer calculated from using each of the first elements as an input character string of the function; calculating second integer hash values for each of the second elements using the function; grouping each of the first elements into at least one group of a set of blocking groups using its first integer hash value; grouping each of the second elements into at the least one group of the set of blocking groups using its second integer hash value; and matching first elements with second elements within each group of the set of blocking groups using a string comparison function.



US10164892B2 Overhead management for virtual machines

Inventors: Francesco Fusco, Thomas Graf, Michael Tsirkin
Assignee: Red Hat Israel Ltd
Status: Grant

A method includes loading a guest virtual machine onto a host system, determining, with the host system, an encapsulation method to be used in association with a virtual network associated with the guest virtual machine, determining an overhead value based on the encapsulation method, determining an adjusted maximum transmission unit (MTU) value based on the overhead value, and passing, information related to the adjusted MTU value from the host system to the guest virtual machine.



US9940344B2 Fractal approach for probabilistic flow cache maintenance

Inventors: Francesco Fusco, Daniel Borkmann, Thomas Graf
Assignee: Red Hat Israel Ltd
Status: Grant

An apparatus sets a layer counter to point to a first layer of a data structure. The apparatus determines the layer counter to reference an overflowing cell. The apparatus increments the layer counter to point to a second layer of the data structure. The apparatus determines the incremented layer counter to reference a non-overflowing cell. The apparatus increments a value of the non-overflowing cell, wherein the first layer is stored in a first cache and the second layer is stored in a second cache, and wherein the first cache differs from the second cache with respect to one or more of speed or size.



US20150046406 Method and device for data mining on compressed data vector

Inventors: Nikolaos Freris, Francesco Fusco, Michail Vlachos
Assignee: International Business Machines Corporation
Status: Application

A method for data mining on compressed data vectors by a certain metric being expressible as a function of the Euclidean distance is suggested. In a first step, for each compressed data vector, positions and values of such coefficients having the largest energy in the compressed data vector are stored. In a second step, for each compressed data vector, the coefficients having not the largest energy in the compressed data vector are discarded. In a third step, for each compressed data vector, a compression error is determined in dependence on the discarded coefficients in the compressed data vector. In a fourth step, at least one of an upper and a lower bound for the certain metric is retrieved in dependence on the stored positions and the stored values of the coefficients having the largest energy and the determined compression errors.



US9286333B2 Stream Compression and decompression

Inventors: Harold Douglas Dykeman, Francesco Fusco, Thomas R. Locher
Assignee: International Business Machines Corporation
Status: Grant

A method for compressing a sequence of records, each record comprising a sequence of fields, comprises steps of buffering a record in a line of a matrix, reordering the lines of the matrix according to locality sensitive hash values of the buffered records such that records with similar contents in corresponding fields are placed in proximity, and consolidating fields in columns of the matrix into a block of codes. In this, consolidating yields codes of one of a first type comprising a sequence of individual fields and a second type comprising a sequence of fields with at least one repetition. The second type of code comprises a presence field indicating repeated fields and an iteration field indicating a number of respective repetitions. Decompression of the records from the block codes compressed above is also described



US8688655B2 Network Analysis

Inventors: Francesco Fusco, Andreas Kind, Marc P Stoecklin, Michail Vlachos
Assignee: International Business Machines Corporation
Status: Grant

A method for providing a compressed index for a stream of binary data records comprises steps of indexing a field from each record in a bitmap index, compressing stored bits in each column of the bitmap index by replacing a group of successive bits with a code and outputting the code. There is provided at least one of a first code for replacing a sequence of a first filling, a literal and a second filling, and a second code for replacing a sequence of a first literal, a filling and a second literal. In this context, a filling is a sequence of bits with the same value and a literal is a sequence of bits with different values.



US8782012B2 Network Analysis

Inventors: Francesco Fusco, Marc P Stoecklin, Michail Vlachos
Assignee: International Business Machines Corporation
Status: Grant

Methods and a device for providing a compressed index of binary records. A method includes: sorting the records by content of a predetermined field of the record, indexing the field from one of the records in a line of a bitmap index, compressing bits in a column of the bitmap index by replacing a group of successive bits with a code, where the sorting includes the steps of assigning, for each record, a hash bucket of a hash table on a basis of a locality sensitive hash function on the contents of the predetermined field, so that the probability for two of the records to be assigned to the same has bucket increases with the similarity of the contents of the predetermined field between the records, and where at least one step of the computer implemented method is executed on a computer device.