logd: prune 10% or 256 entries max

    return len;

}

// If we're using more than 256K of memory for log entries, prune

// at least 10% of the log entries. For sizes above 1M, prune at

// least 1% of the log entries.

// Prune at most 10% of the log entries or 256, whichever is less.

//

// mLogElementsLock must be held when this function is called.

void LogBuffer::maybePrune(log_id_t id) {

    size_t sizes = stats.sizes(id);

    unsigned long maxSize = log_buffer_size(id);

    if (sizes > maxSize) {

        size_t sizeOver, minElements, elements = stats.elements(id);

        if (maxSize > (4 * LOG_BUFFER_SIZE)) {

            sizeOver = sizes - ((maxSize * 99) / 100);

            minElements = elements / 100;

        } else {

            sizeOver = sizes - ((maxSize * 9) / 10);

            minElements = elements / 10;

        }

        size_t sizeOver = sizes - ((maxSize * 9) / 10);

        size_t elements = stats.elements(id);

        size_t minElements = elements / 10;

        unsigned long pruneRows = elements * sizeOver / sizes;

        if (pruneRows <= minElements) {

            pruneRows = minElements;

        }

        if (pruneRows > 256) {

            pruneRows = 256;

        }

        prune(id, pruneRows);

    }

}